Charisma needs more importance, definitely. I like the idea that charisma:
Lowers prices of hiring new heroes
Army moral effects
Diplomacy bonuses
Quest bonuses
More quests from people
Lowers store prices
Increases fertility rate
Possibly city bonuses (prestige or gold, from "governing" or something)
It just needs more function, imo.
Solid thought here.. Have a hero with high charisma in a stack then stack gets moral bonus..
diplomacy bonuses speak for them seleves
High charisma hero completes quest gildar/exp bonus.
better prices of the shop nuff said.
and for the sovereign even better..