See the problem here is that you seem to be unable to words good and simultaneously seem inclined to make assertions about d20 and "D&D" that seem to indicate you have somewhere short of no deeper understanding of how it works.
This results in you sending deeply contradictory mixed messages about your premises, goals, and methodology.
Take for example, even your opening sentence...
codeGlaze wrote:Or something akin to a skill. However your imagined system works.
Which is a complete non-sequitur that doesn't even seem to know that even the known existing spectrum of "imagined systems" defines "skill" so incredibly diversely that you just said just short of fucking nothing, hell LESS than nothing.
You also then, and again later, fail to clarify the vague and muddled implication that you want to
remove the Charisma base attribute and replace it with... ???
But more impressive, and deeply problematic, is this statement and later "clarification".
codeGlaze wrote:From a d20 perspective I think it pretty easily fits in that Gray space most of the useful skills reside in. The space of "non combat proficiencies" that can also be creatively used in combative situations...
...@Gray-areas : Tumble, obviously, is a good example. But yes, intimidate, use rope, slight of hand, jump, balance, ride, use rope, concentration, disable device, handle animal, bluff, perform can all be creatively used in combat. Some requiring more creativity than others.
Now aside from the fact that use rope really isn't good enough to warrant mentioning twice... your list, and your stated reasoning behind what you think are "the most useful skills" is... bullshit.
The most useful skills in d20 are useful because the skill, or at least a minimum of one important function it performs
does NOT reside in a gray space.
The most useful skills in d20 are
not useful because of their potential for "creative" use, they are useful because of their
boring and predictable predefined formal functions.
The most useful skills in d20 are
not that way because they are "non-combat proficiencies that can also be rarely used in combat" they are options that provide direct commonly combat relevant effects. They MIGHT also have non-combat applications, or not, the non-combat bit
doesn't particularly matter in rating them as a "good skill" for d20.
Creative use of skills is pure mother may I. It can have value of sorts, but it is NOT the definitive feature of "the good skills" in d20. If anything the more a skill relies on mother may I, the WORSE that skill is. Because mother may I is equally worthwhile or worthless and available on EVERY skill, value and mechanic in the game already for free. It is the predefined formal mechanics tied to certain skills that are the ONLY possible measures of objective comparable value be it good or bad
period.
That point on it's own pretty much requires you to provide a multi page thread of ranting about how much you like basketweaving to even attempt to pretend you've justified your scheme for valuing d20 skills. But then you also said...
codeGlaze wrote:I could see charisma attacks being defended with a will save in d20 terms. Other skills could provide bonuses or possibly act as a stand-in defense if high enough or applicable.
Which is very WTF don't you know how these numbers even interact? Don't do that. Never do that.
But it doesn't end there. Because when asked "what the hell is different about this Charisma skill... compared to existing Charisma based skills?" your answer was...
codeGlaze wrote:@diplomacy, et al. : Using a skill-groups variant rule would probably be the most effective use of a CHA skill. With charisma being the umbrella skill.
Worst case scenario, charisma and diplomacy give each other "synergy".
Which tells us god damn nothing about the differentiation whatsogodamnever. As far as I can tell your answer to "what does this skill do different to the existing charisma skills?" was "maybe it does exactly the same thing as all of them at once OR
maybe it just doesn't do that!"...
Then, ultimately, you then end up with this rambling clanger...
codeGlaze wrote:This actually stemmed from mentally separating the combat mini-game from the social mini-game. (Primarily because a decent social subsystem doesn't really exist.)
I think the premise could work especially well with DnD specifically because a good social mini-game does not exist. This, imo, alleviates two big sore-thumbs.
1) The primary subsystem people interact with in d20 is combat. CHA is an edge-case combat affecting ability.
2) This allows for easy expansion on CHA if a working social game is ever stitched together, without having to shoehorn shit in up-stream. Because it's not really connected to the combat ability array.
d20 already HAS charisma skills. They are
already somewhat significantly divorced from the combat system. They already do what your proposed skill does, or maybe not, who fucking knows, and all in all baring a few notable flaws in the skills themselves and the overall skill system itself they perform pretty much adequately if your plan for social mechanics is "minor mostly informal after thought".
Your plan to "separate" them from combat is to... make them effect combat? Only just perhaps sometimes in "creative" ways, only even though its "edge case" this "creative" effecting combat thing is the primary (and to some extent only) defining feature?
And this "change" will be achieved... by not really changing anything. Except maybe completely breaking the numbers by rubbing saving throws against skill checks without apparent consideration of what that might result in.
But most importantly, fucking hell NO this does not make it easy to
later on turn "Charisma skill" into a working separate social minigame.
Firstly you aren't making any kind of coherent change to start with so "Status quo plus maybe nothing or perhaps WTF?" isn't even really a step anywhere period. But also even if it were you cannot lay the foundational mechanics for a complex and rewarding "minigame" when you don't even have the beginnings of a plan for what that is even supposed to do or look like.
Once you've gotten past the point of "insert minigame here" you need to actually start building the damn thing or GTFO, throwing in a single utterly incoherent mechanic completely at god damn random and calling it a step forward is not actually in any way shape or form a part of that process.