As proposed in the 'house rules' thread, we started talking about how great it would be to create a new sub-system of D20, that evened out many of our gripes with the system.
Here's an idea that we can work with, and go from there:
Primarily, everything is based on 'skills' - players get X skill points to spend per level. The max rank is Level + Y. When leveling up, players pick an ability, so they'd be a Strong Hero 1, Agile Hero 3, etc. When taking a level in that alignment, players get an extra Z bonus skill points for use in that skill.
Players also get feats - Used for either general feats, or for class features.
Strength -
Light Melee Weapons (Daggers, Short-Swords, throwing weapons, etc.)
Medium Melee Weapons (Axes, maces, longswords)
Heavy Melee Weapons (Basically everything 2-Handed.)
Exotic Melee Weapon (_______)
Shield Proficiency:
Melee Hit Chance
Agility -
Evasion (Reflex Saves)
Dodge (AC)
Sleight of Hand (As the skill)
Critical Hit Chance
Ranged Hit Chance
Stealth
Endurance
Hit Points
Action Points
Vitality Points
Fortitude Saves
Concentration Checks
'Overcasting'
Mysticism - (Players get spell-points equal to their ranks - spells have 'color-coded' casting costs. For example, magic missile is an energy spell that costs E, Cure Critical Wounds costs BBBB+3. This means that casters are more flexible, but not as much so as the normal spell-point variant would be.)
Boon Magic
Nature Magic
Death Magic
Energy Magic
Control Magic
Magical Training (Save DCs)
Focus
Will Saves
Perception
Save DC
Spell Resistance
AC
Posts
D20 is pretty well established as having certain qualities and features; role players need to play a broad variety of RP systems for different types of gaming, rather than modifying one to attempt to be everything (and if you ask me it's not a good sign that a system needs to be 'modded'- with substantial edits/additions to get variety out of it- beyond just house rules).
So, Legoman: I take it "Mysticism" is a more baseline version of the "Willpower" stat in the subsystem I mentioned earlier, tying in elements of Charisma? I like the outline you've given Focus there, although I do wonder what part it could play in determing, say, to-hit chances, especially for ranged combat.
Appropriate to the recent release of "Unearthed Arcana", our games tended to combine Vigour (called vitality in your proposed outline, right?) with Action Points. Everyone tended to have a lot more Vigour than normal so although they still had an AP stat, that never reduced: it just determined how much Vigour they could use in the same place as an AP.
For example. Pistol wielding madman (excuse the D20 Modern reference) shoots and hits. Fighter loses 7 Vitality (and only takes 2 lethal, direct-to-HP damage because the pistol is obviously quite crap)- and then in response expends further Vitality to get a solid bonus to running down the corridor and hitting the man in the face with his bat
I especially like it's implementation in Paranoia, as Perversity points - You get a certain amount per level, plus some for entertaining things, and you can use them to make rolls easier. For example, I have to roll under my weapon skill of 13, so I'll spend 4 perversity points to bring it up to 17, all but ensuring my success.
I like the idea of action points/vitality points going together - what about tying them to other things, like magic? I'm rapidly seeing that with the tome of battle and close adherance to the wealth-by-level guidelines, magic isn't wtfpwn anymore. (A 17th level warblade has a maneuver that adds 100 damage to his next attack... While power-attacking with a +4 , 2h weapon, that's enough to put a caster solidly into the red.)
What about a system that ties magic, ToB-like maneuvers, vitality, and the standard action points all together into one unified 'point' system? Say, a character gets a certain number of action points per character level - if they have a high 'Magic' score, for instance, it costs far less AP for them to cast a spell, whereas if they have a high weapon's skill, it costs far less for them to do exceptional damage.
The advantage of this is that characters could be remarkably simple to create and understand, and that both specializing and generalizing would be useful. Also, every character would be capable of both magic and martial maneuvers.... if they were willing to pay the cost for it.
If you're trying to break the system down into classlessness... D20 really isn't the system for it, I don't think.
Action points can be cool, though, but my favourite use of them was presented in the WoW d20 book: You can expend an action point to temporarily take over the narrative.
"The necromancer, cackling madly behind his altar, begins waving his hands in the air, preparing to -"
"I spend an action point. I'm going to hurl my axe and sever his arm."
"- scream in agony, clutching his bleeding stump."
And the arm severing moment is just plain awesome: we'd have called those "Fate" points or something similarly daft. Our AP were a lot less interesting
But I can't say I was much good with D20 versions (anyone seen Cryptocult? It's probably online somewhere) that try and unify everything into one Action derivative. Ultimately it works just the same as having HP/VP/PP (or whatever the setting calls for) because of the different rates actions reduce them at, but for some reason it never appealed.
By the way INNS, although I've tried "classless" D20 games before, I'd have to agree that the system doesn't quite suit it. Feats always seem best-designed for class specifics, and although a class-based system isn't as freeform it does force people to make some interesting decisions during PC development!
My proposed ones:
Eh, don't like the idea of setting out to be "better than standard D&D". Best bet with any interchangable feature set is just to admit that you can't do everything perfectly, but to aim for something different to the original's purpose.
It's always difficult to perfectly balance things, but I did see this (frankly overly simplified) system whereby all "spell levels" were retconned into Epic-style DCs. It was pretty neat and very well balanced, but every single power was too much like "earlier power +".
Vitality/stamina/AP/vigour (whatever!) ultimately ends up like a spell variety anyway in the games I've seen, because PCs tend to expend their AP for borderline-magical bonuses. It was a great equaliser, especially with the aforementioned DC-based system.
And not to forget the power the GM has over any generic dodgy situation: although, rather fortunately, I rarely played with GMs who possessed an overly antagonistic mentality.