When creating a character, there are two major considerations: Roleplay and Combat.

For the most part, Roleplay is more determined by how you play than your specific set of combat skills. Exceptions occur - it's silly to play a character who is constantly jumping into the thick of combat if you're a mystic with only a few hitpoints - but for the most part your class and race are chosen by how you want to roleplay, then skills fit in from there.

Some basic combat terms:
DPS: Damage per Second - basically, the ability to do a large amount of damage in a small amount of time
Tank: The person who is taking the brunt of the melee attacks. Typically the character with the highest defensive abilities or the most HP. Usually Warriors get this job. Commonly mistaken for the character who is responsible for doing the most damage.
Assist: Any melee character who is engaging the Tank's target but is NOT the tank. Usually Soldiers and Spies fall into this category, sometimes Psychics.
Psychic: Character with at least some degree of Psionic powers
Healer/Musician: Character with at least some degree of Harmonics powers or in some rare cases a character with some other form of healing such as chemistry

Some notes on combat from different classes perspectives:

Warrior:

Contrary to popular belief, a Warrior is NOT there to damage the enemy. Despite having the best face-to-face melee skills, the value of a warrior lies in their ability to hold an opponent (or even a group of opponents) in place so your team can pick them off. You might be able to do 10 damage at level 10, but the level 10 mystic behind you is doing 50 with each apprentice packet.

Advantages:
Warriors have the best HP in the game. Coupled with decent armor and some basic combat skills, you can easily keep the enemies tied up. You can swing for higher damage than any other class as many times as you want, and since you never "run out" of damage you're a constant threat. Skills like Riposte and Deadly Strike increase your offense abilities considerably, although you're still one of the lowest DPS classes.

Disadvantages:
Most Warriors have minimal mystic skills, this includes Resists (although many groups will stack as many resist powers and items on the tank as possible). If you go down for more than a few seconds, your party probably does too. Your damage is high in melee, but compared to most other classes it kinda sucks. You will die, and you will die often, which can be frustrating.

Soldiers:

Most players don't like playing a soldier because it relegates you to a support role. Despite their superior defense skills, the lower HP makes you a poor choice for tank, and your focus on ranged weapons makes you ineffective in melee. However - you have one of the most powerful abilities in the game: The ability to decide who takes the damage.

Advantages:
Soldiers have every defensive skill at low cost. If used properly, a soldier/warrior team can mitigate almost all incoming damage, making the warrior able to survive indefinitely. In a pinch, you can sacrifice yourself in order to keep other characters (especially the healer) alive long enough to heal you both (and probably the warrior too). Alternatively, you have access to some of the best ranged combat in the game. Armed with a decent gun you can severely damage most creatures before they get into melee range.

Disadvantages:
You will probably never kill anyone. You will die a lot. You won't reclone if you play smart though, because your timely sacrifices will keep other teammates alive long enough to save you. You have to rely on tactics and guerilla warfare to survive, because once something gets inside melee range you're not damaging it anymore (although you can probably survive long enough to run)

Spies:

Spies have the highest melee damage capacity in the game. At level 10, you are capable of doing a whopping 18 points of damage with every single strike. However - you have low hitpoints and make a crappy tank, so you better be travelling with a group or using "hit and run" tactics.

Advantages:
You can do more damage than anyone else. Period. All day long. 18 basic, 18 basic, 18 basic, 18 basic as many times as you can swing. You also have access to Use Poison for dirt cheap, and since you're behind your target anyways you're almost guaranteed to get a good hit in. Mystic skills are cheap, so you can augment your natural skills with some mystic skills for some deadly combinations. You also have access to streetwise and encrypt/decrypt, along with pick locks and disarm/arm traps making you extremely desireable in non-combat encounters. Piercing attacks go clean through armor. You get assassinate and smite a full level earlier than warriors and soldiers.

Disadvantages:
While spies have access at relatively cheap costs to virtually every skill in the game, they have minimal hit points and almost no core class-defining combat abilities outside of assassinate. Spies also have to be behind their target for most skills, limiting their tactical flexibility. Because of these issues, spies are relegated to "assist" roles in most combats. Limited hit points allow you to survive long enough to escape, but in a protracted fight you will probably die (especially since face-to-face you're back down to 2 damage)

Healer:

Often considered the most necessary component of every team, the healer has a critical role in keeping the party alive. Coupled with anti-necromancy abilities the healer has a high value in a team situation.

Advantages:
Healing. Lots of it. You can keep the party alive as long as you have powers left, and you are usually well-guarded by your teammates. Against Undead you have some powerful powers at your disposal.

Disadvantages:
In order to be a good healer, you have to focus on it, leaving your damage skills seriously lacking. You will do minimal damage to non-undead in combat. You have almost no hit points, so if something starts attacking you, you'll probably die. Most likely you won't kill more than a couple things per game. Melee skills are almost non-existent, even at high levels. You also have to be careful to budget your powers so you don't run out.

Psychic:

Psychics are the highest DPS class in the game. By level 10 you can be doing 150 points of damage with a single power, and you've probably got a lot of powers. You can increase your melee skills to do impressive damage, but you have to work harder than warriors for the same overall effect.

Advantages:
Damage. Psychics are the masters of dealing damage to opponents. Most "boss" encounters will fall to you. There is no other class that has more offensive power than a psychic. You also have a few key defensive abilities (such as resists) that can bolster either you or a teammate.

Disadvantages:
Without expending extra powers, you have almost no hit points. Powers like Ego Boost make you tougher, but increase the odds you'll die from specifically targeted attacks (such as mystic powers). You lack tactical flexibility and if you don't budget your powers, you'll be left completely defenseless.

Projectionist (mystic):

Projectionists are a support class who specialize in making combat happen on their terms. A projectionist can use powers to increase the defenses of their team, immobilize key opponents and destroy constructs. They are also useful for utility purposes, such as using mass distortion or mystic glue to alter their environment.

Advantages:
No other class has the tactical flexibility of a projectionist, and few are harder to kill. Although they have minimal hitpoints, they have a wider array of defensive powers than soldiers and have a high degree of utility. In non-combat encounters they compliment spies well and between those two classes most environmental encounters are easy to overcome.

Disadvantages:
Projection, more than any other mystic class, has to learn to budget their powers appropriately. Some abilities are only available on certain teirs, and while a psychic can choose to use a lower damage spell on an easier target, a projectionist might not have a "weaker" or "stronger" ability on another tier to choose from. Most defensive skills are either limited in number or require forewarning, making surprise attacks particularly deadly.

Engineers:

Without Chemistry (or at least the ability to use it) most engineers have a minimal role during combat. However, their skills allow them to rebuild weapons, modify weapons and armor to make it stronger, and they can effectively become a weaker version of any class they choose on a day-to-day basis. Missing a healer? Load up on chemical healing. Don't have a psychic? Make extra poison for extra damage. Missing a warrior? Buff the armor on a soldier, power up his weapons and call it good.

Advantages:
Engineers can do anything. If they're not filling in for another class, they can use their skills to make every other class more effective than it already is. On environmental encounters, they have several skills that increase their odds when dealing with technology. Traps and locks fall quickly to them. You can build traps, which are virtually unresistable, but they require advance placement which usually limits their effectiveness on modules.

Disadvantages:
You have no real combat skills of your own outside of the VERY limited chemistry. Your skills usually require money to use, so a bad or nonunderstanding group can cause you to lose money extremely quickly. You are always relegated to the support role.

Tactics:

Assuming one of each of the above in your group, the most common tactic when dealing with combat encounters is as follows:

Warrior picks a target. Everyone fights it. Projectionist disables other targets so fewer things are coming at you. Psychic either assists with weapons (doing their best to not get hit) or powers (keeping conservation in mind). Soldier deflects the worst hits from the Warrior, nullifying with parries or combinations of other skills. Spy runs up behind and deals out damage. Engineer assists wherever he can, while the healer keeps an eye on peoples' health (especially the tank).

Core Fundamentals:

If the Healer or Tank dies, the party wipes. Typically some form of backup healer should be in place.

DO NOT split the party. Ever. Splitting the party means the monsters can pick you off in smaller groups.

Healer and Tank should have a system in place for healing. The Tank should know how much the Healer can heal for, and how long it takes them to do it. Tank should request healing when they need it, rather than the Healer waiting until he falls OR wasting heals on a tank who might not need it yet. As with anything else, communication is key.

If you aren't comfortable in support roles, and want to play the "glory" parts, play a psychic, spy or warrior. Any other class and you'll just piss people off since you're usually meleeing when you should be doing something else. A quality support character will earn the respect of their party without necessarily having to actually be doing any damage to opponents because good players recognize the value of support characters.

Mystics: DO NOT pop off powers at everything that crosses your path. By the end of the day you'll be regretting it. Higher level mystics might do it, but some of them have enough powers to get away with it. Learn to budget. A good rule of thumb is to assume you'll have 10 fights on a game day, and 30 on an event day - budget appropriately. If you've only got 10 powers, that's only 1 per fight. Typically most modules put the toughest encounter at the end, so you'll need to allocate a few (or most) of your powers to deal with that.

Don't die.

Don't try to tank as an engineer, and don't hide in the back if you're a warrior. Yes, if you're a level 1 warrior you'll die, and you'll die a lot. That's what the healers are for. Deal with it.

Most NPCs have vulnerabilities. Learn what they are. Sometimes some things can only be killed certain ways, learn the best ways to kill each thing.

Skill Selections:

Skill selection is one of the most important aspects of creating a character, and is arguably the most key element that determines whether or not you will survive.

Keep in mind that taking skills that fall outside your normal bracket makes you increasingly more flexible and allows for tactical advantages that you can't normally get. Also keep in mind that some races can modify your skill selection options.

As a general rule, figure out what you want to have towards the end of the game before choosing your class. This will change as you play the game, but it's a good idea to have a plan for where you're going.

With those things in mind, here's some canned Level 10 characters that fit into some combat stereotypes. Skills are laid out in the format "Skill (cost, running total)":

Warrior - General:
Melee Specialist (5, 5)
Paired Weapons (5, 10)
Melee Mastery x4 (48, 58)
Deadly Strike x2 (10, 68)
Maim Strike x1 (4, 72)
Roll With Hit x4 (8, 80)
Guardian (3, 83)
Mystic Parry x4 (12, 95)
Riposte (4, 99)
Frenzy x1 (1, 100)
This character can function well as either an assist or a tank. Although lacking in direct damage, this character has a good variety of special attacks and defenses.

Warrior - Tank:
Melee Specialist (5, 5)
Shield (6, 11)
Guardian x2 (6, 17)
Durability (2, 19)
Roll with Hit x10 (20, 39)
Riposte x4 (16, 55)
Evade x2 (16, 71)
Melee Mastery x2 (24, 95)
Frenzy x5 (5, 100)
Although lacking in damage, this character can nullify most of what hits them. In later levels, mystic and massive parries would round out the defenses, while extra melee masteries would increase damage.

Warrior - DPS:
Melee Specialist (5, 5)
Paired Weapons (5, 10)
Melee Mastery x7 (84, 94)
Deadly Strike (5, 99)
Frenzy (1, 100)
This character has high damage and high hit points, making it an adequate tank but well-suited to frontline combat. While not as potentially damaging as a spy, the higher damage coupled with the warrior's natural hitpoints make this character able to survive protracted fights in combat and dish out as much as they take.

Soldier - General:
One Handed Melee (4, 4)
Ranged Specialist (10, 14)
Paired Weapons (5, 19)
Ranged Mastery x4 (48, 67)
Guardian (3, 70)
Smite Shot x2 (10, 80)
Deadly Shot x2 (10, 90)
Ranged Parry x2 (8, 98)
Roll with Hit x1 (2, 100)
This character has a good balance of shooting skills, and is set up well to take specialized parry skills at level 10. At that point they can fill either an assist role in combat or help peel damage from the tank depending on the situation.

Soldier - Ranged Assist:
Ranged Specialist (10, 10)
Paired Weapons (5, 15)
Ranged Mastery x6 (72, 87)
Smite Shot x1 (5, 92)
Deadly Shot x1 (5, 97)
Break Shot x1 (3, 100)
From the rear line of combat, this character is capable of doing an impressive amount of damage at the cost of minimal defense.

Soldier - Damage Mitigation Assist:
One Handed Melee (4, 4)
Offhand Specialist (7, 9)
Roll with Hit x12 (20, 35)
Guardian x3 (9, 44)
Dex Armor x4 (40, 84)
Evade x2 (16, 100)
This character is functionally invulnerable and can protect up to three other characters with guardian abilities. Starting at level 10, they should pick up mystic and massive parries to increase their mitigation abilities.

Spy - General:
One Handed Melee (5, 5)
Backstab x4 (48, 53)
Vital Stab x2 (8, 61)
Assassinate x2 (10, 71)
Disguise (5, 76)
Use Chemistry (6, 82)
Arm/Disarm Traps (4, 86)
Pick Locks (4, 90)
Streetwise x3 (9, 99)
Surprise Attack x1 (1, 100)
This is a fairly decent spy build that leans towards combat. Streetwise and encrypt/decrypt would be good skills to buy from this point on.

Spy - Assassin:
One Handed Melee (5, 5)
Backstab x5 (60, 65)
Assassinate x2 (10, 75)
Vital Stab x2 (8, 83)
Use Chemistry (6, 89)
Arm/Disarm Traps (4, 93)
Disguise (5, 98)
Roll with Hit (2, 100)
This spy is completely built around high damage in combat. Paired Weapons and more Backstabs will increase the damage potential.

Spy - Intel:
One Handed Melee (5, 5)
Disguise (5, 10)
Use Chemistry (6, 16)
Pick Locks (4, 20)
Arm/Disarm Traps (4, 24)
Streetwise x11 (33, 57)
Encrypt/Decrypt x11 (33, 90)
Paramedic (4, 94)
Pistols (6, 100)
This spy is set up for tactical support roles and more RP than actual combat. Although of limited combat use, this character is able to do work in infiltration, traditional assassination (using poisons, setting traps) and can support combat either with swords or pistols (likely enhanced) or assisting Healers (with chemistry or paramedic).

Mystic - Psychic:
One Handed Melee (7, 7)
Mental Focus (4, 11)
Apprentice Psionics x10 (10, 21)
Detect Mystic (2, 23)
Journeyman Psionics x10 (30, 53)
Dispel Mystic (4, 57)
Master Psionics x8 (40, 97)
Mystic Juggling (3, 100)
This character is a psychic in the most raw damage sense of the word, although lacking in flexibility. Physically fragile, this character must rely on burning enemies down before they can react.

Mystic - Healer:
Simple Melee Weapons (1, 1)
Tuning (4, 5)
Apprentice Harmonics x11 (11, 16)
Detect Mystic (2, 18)
Journeyman Harmonics x10 (30, 48)
Dispel Mystic (4, 52)
Master Harmonics x9 (45, 97)
Mystic Juggling (3, 100)
This character is a raw healer. Although this character has a minimal role outside of healing, their contribution to the party is absoloutely critical to group survival.

Mystic - Projectionist:
Simple Melee Weapons (1, 1)
Barrier (4, 5)
Apprentice Projection x11 (11, 16)
Detect Mystic (2, 18)
Journeyman Projection x10 (30, 48)
Dispel Mystic (4, 52)
Master Projection x9 (45, 97)
Mystic Juggling (3, 100)
This character is extremely tactically flexible, although they don't have the raw damage capacity of most of the other characters.

Mystic - Hedge Mage:
Simple Melee Weapons (1, 1)
Mystic Juggling (3, 4)
Tuning (4, 8)
Mental Focus (4, 12)
Barrier (4, 16)
Apprentic Psionics x11 (11, 27)
Apprentice Harmonics x10 (20, 47)
Apprentice Projection x10 (30, 77)
Detect Mystic (2, 70)
Journeyman Psionics x7 (21, 100)
Although heavily limited in raw power, this character has moderately high damage, some healing abilities, and a high amount of utility.

Engineers:
I thought about canned characters here, but the reality of the situation is that engineers are never as effective in combat as the other classes. Engineers are used for both their technical/cracking skills (defeating traps, hacking computers, etc) and creating armor/weapons to enhance themselves and others. There is a functionally limitless number of different combinations of skills, but most engineers choose to take a weapon skill (generally ranged) a combat skill or two (particularly ranged or melee mastery), a decent amount of chemistry and then skills like jury rig, trap design, weapon design, etc. Engineer Skill Selection could almost be an article in and of itself.

As a final word: Don't use any of these characters. While reasonably effective, most of these characters can't do anything outside of their assigned roles and lack any kind of real personality. Most people don't focus on one thing solely to the extent of not taking up anything else. In order to feel like a real person, your character should have a realistic set of strengths and weaknesses. While it is almost impossible to be good at more than a few things in Pathways, it's fairly easy to pick one or two things and be reasonably good at both.

The best way to design a skill program is to answer the following question: When my character isn't going out on adventures to save the world, what is he/she doing? My character happens to be an archaeologist, so despite being a warrior I have disarm traps and pick locks, and I intend to get ID writing and ID items as soon as I can save up the points for them. It's not that useful for combat, but the skills come in handy and they're appropriate to the character. One of my Scions characters is basically evil and completely selfish - while first aid (basically paramedic in Pathways) would be an effective choice given his combat role, it just doesn't make SENSE in the character concept. Have a reason for every skill choice that extends beyond "I wanna be a badass..."