This is just for fun, but i wonder what would happen if d&d had the following six attributes:
- strength - (merged str and con)
- dexterity (thieves tools, sleight of hand, finesse and ranged attacks, etc)
- agility (ac, initiative, stealth, acrobatics and saving throws)
- perception (replaces int and all knowledge skills plus perception rolls)
- willpower (saving throws, wis spellcasters, etc)
- cha (same except includes insight)
Characters would be more MAD to be sure. But would they be more interesting?
Alternative framework that i have found to be very manageable in other systems...
PHYSICAl
Strength - power available for physical tasks
Constitution - resistance/endurance available for physical tasks
Dexterity - finesse, precision and quickness available for physical tasks
MENTAL
Intelligence power available for mental tasks
Wisdom resistance/endurance available for mental tasks
Wits finesse, precision and quickness available for mental tasks
They key with these is that the skills/proficiencies bonus would be more like they are with tools - not tied to a given attribute even a little but dependent on the task, circumstance and situation. they should be quite broad in scope because the marriage of skill+attribute would be the real "task"
Now, arguably one could separate out a third set of characteristics for Social (Charisma, Faith, Empathy) is one felt having the social falling under mental to be too off-putting or otherwise distasteful.
As far as magic systems would go this could also allow quite firm differentiation between "learned magic" and "soul magic" (divine or instinctive arcane.)
But giving each "pillar" so-to-speak its own trio of power-finesse-defense opens a lot of very clear, simple and still dynamic choices.
In a 5e specific take:
Add the three social using the DMG options for adding abilities.
Pretty much let saves be defended in each group by the resistance stat.
Pretty much let save DCs be set in each category by the POWER stat.
Pretty much let damage bonuses be based off power.
Pretty much let to-hit and all sorts of finesse abilities rely on the finesse stat. For example, if you have sculpt spell for your fireball, you have to use Finesse not Power for the DC.
The current "charisma casters" use the "social" trio, the existing INT casters use the Smarts trio and its up to the Gm to determine how they want to divide the divines but my initial preference would be to put them under social - covering their strength and conviction as well as their ability to be compelling and convincing. (Though some divines could go the other way - a god of magic might shift the whole trio over to the smarts.)
Arguably you could say CON helps HP" and "Dexterity helps AC" as it currently works without any serious problems. (As well as also perhaps applying that division to the other trios if you wanted to build up more of a "combat sub-system" for those trios.)