A crowd in a tavern and a gathering of diplomats probably react very differently to the same "combination of physical appearance, force of personality, leadership skill, smooth talking, and apparent moral authority." In some specific places and situations, a low charisma character might even have a social advantage over a higher charisma character.
Two folks with an identical Charisma score, but each having a different weighting of those five factors should evoke different reactions to the same situation.
I personally go almost entirely for personal strength and social skills when I think about Charisma as a character attribute. ... I think Charisma as a social stat, rather than physical appearance stat, is much more interesting, and thus, I play it like that. Attractiveness through words and character, rather than flesh, is the way to go.
We have no comeliness Stat in the NWN nights engine....