haters
This.
Normal people tend to hate complex games yet they still are the most interesting to min-max
Furthermore, additional attributes like charisma and intelligence could be heavily used in Strategus.
However, they are also useful for cRPG :
Let's say Int is basically a remplacement for "convert attributes to skill points", with a new skill attached to it. Like "Trading" that could reduce the item prices and your upkeep by 5%. It could also reduce a marketplace fee if that is ever implemented.
About Cha, it could be used as a limit for the commander's voice commands (attack, shoot, hold...), influence autobalance (more Cha could mean you gather all the people that have your banner more easily) so it is useful for commanders and nearly no one else.