New example of what a potential class will look like (still not by any means set in stone):
The Asskicker: You are a mercenary, or a soldier, or a martial artist of some kind. You contribute to the party by being a skilled physical combatant who does damage primarily through martial skill. At higher levels you may get some magical enhancements or have been taught a few skills to help you keep up but you're mostly a mundane warrior in the beginning.
Alignment Unrestricted (Alignment will mostly be less a restrictor of your behavior, and more of a proclamation of which of the Powers That Be you have aligned yourself with. You're still allowed to be a hypocrite, depending on the nature of your particular Gawd/Pantheon.).
Base Attack Bonus +2 (BAB is added to attack and damage rolls, as well as Initiative rolls. BAB is set at Level 1 and determines what combat maneuvers you have access to and how well you can use them. Attempting a maneuver against someone with a higher BAB provokes an Attack of Opportunity. Initially BAB ranges from +0 to +2, but can rise with rare Class Abilities.)
Base Defense Bonus +2 (BDB ranges from +1 to +3. You BDB is added to a certain number of defenses equal to your BDB. As an example if your BDB is +1 you may choose one Defense to get a +1. At +2 you choose two Defenses to add +2 to. Defenses include Armor, Dodge, Durability, Perception and Resolve. Armor is the passive chance your Armor intercepts attacks. Dodge is your ability to avoid attacks, dive for cover, etc. Durability is a measure of your ability to just shrug off poison, disease, status conditions, etc. Perception is your defense against being ambushed or lied to. Resolve is your mental determination and ability to shrug off psychic attacks. Like BAB there are rare opportunities to increase it via class abilities. BDB plus your Constitution Modifier is also added to your hit points at each Level)
Base Skill Bonus +1 (BSB is a measure of your skill level, and ranges for +1 to +3. You have access to all untrained skills, rolling 1d20 plus the appropriate Ability Modifier. You choose a number of skills that require Training to use equal to your Int Modifier. For example if your Int Modifier is +3, you have access to all Skills that don't require Training, and Three Skills that do. You may choose a number of skills equal to your BSB to add your BSB to (these are skill specializations). For example if your BSB is +1 you choose 1 Skill to add +1 to.)
Base Class Damage 1d8 (Damage for non-special attacks is determined by Class, not weapon)
Base Class Armor +4 (Armor Bonus is also determined by Class. Use of Shields gives an optional Parry Defense).
Key Ability Choose any Ability Modifier to increase by +1. This will be the stat your class abilities key off of, as well as your attack and damage rolls. Str based Asskickers are brutes who rely on physical power. Dex based Asskickers rely on agility and quickness. Con based Asskickers are tough guys who are defensive tanks. Int based Asskickers are tacticians and military leaders. Wisdom based Fighters are generally ranged combatants. Cha based Asskickers rely on misdirection and intimidation. Each of these paths lead to different class abilities.
Hit Points: 10 plus (Con Modifier) plus (Base Defense Bonus), with an additional (Con Modifier plus BDB plus 2) per Level.
Journeyman (Levels 1-10): Gain 1 Feat and a new class ability at each Level. Feats can upgrade a Class Ability, or give you new options entirely. Give a permanent +1 Bonus to any Ability Modifier at Levels 4 and 8 (maximum modifier is +4, plus or minus Racial Modifiers). Upgrade BAB, BDB or BSB by +1 at Level 6 (max is +4). Class abilities gained at these Levels will tend to be basic class abilities, and depending on what you choose, you get a sort of PrC at Veteran Levels.
Veteran (Levels 11-20): Gain 1 Feat and a new class ability at each Level. Give a permanent +1 Bonus to any Ability Modifier at Levels 12, 16 and 20. Upgrade BAB, BDB or BSB by +1 at Levels 12 and 18.
Epic (Levels 21-30): Gain 1 Feat and a new class ability at each Level. Give a permanent +1 Bonus to any Ability Modifier at Levels 24 and 28 (maximum score is now +6 plus or minus racial modifiers). Upgrade BAB, BDB or BSB by +1 at Levels 24 and 30 (max bonus is now +6). Think of Epic Levels as Epic PrC's.
Starting Ability Modifiers will be +2, +2, +1, +1, +0 and -1. Apply Racial Modifiers and add +1 to your Key Ability. Abilities will be the traditional 6 used by D20.
Trained or Untrained Ability or Skill Checks are 1d20+Ability Modifier. Skills you choose to specialize in are 1d20+Ability Modifier+BSB.
Attack rolls are 1d20+Key Ability Modifier+BAB.
Damage rolls are (Class damage die)+Key Ability Modifier+BAB.
Initiative rolls are 1d20+Key Ability Modifier+BAB.
Defense are 10+Ability Modifier (Con for Durability, Dex for Dodge, Wis for Resolve and Perception. Armor is 10+Base Class Armor Bonus). At least one of these Defenses will be 10+Ability Modifier+BDB. Some classes will have other Defense Options like Parry.