Generally, the personality of an AI goes along with its traits. For example, Isabella is spiritual, and gets a production bonus for temples. If she got the AI of an AI who didn't focus on religion, this would be wasted
If Monty got the personality of Gandhi, isn't his Aggressive trait wasted?
Thoughts?
Well, Monty and Gandhi aren't the best examples to use. Both are Spiritual, so things are even in that regard, and you don't have to warmonger to take advantage of Aggressive; a peaceful builder Monty could build up quite a good defensive force, and all those cheap barracks and drydocks would help his power rating and get most of the other AIs to leave him alone.
But I see your point. The Charismatic trait really requires warmongering to leverage it, and Imperialistic even more so. The traits would be wasted on a more peaceful personality. But who's to say another civ, or you, won't force them to leverage the trait they're reluctant to use?
As others have said above, the setting makes the AI less predictable to you. In fact, I've found you're at an even bigger disadvantage unless you play with this setting on a lot (even all of the time), because you keep
expecting the AI civs to fall into their usual patterns of behaviour--and then they don't!
And I don't think it's easy to determine who's who early in the game or even later on. Sharing a religion with a belligerent AI leader can often make them into a pussycat. You might be sharing Hinduism with Mansa and thinking he's the same old Malinese, but then he goes off trouncing his neighbours at the slightest provocation and asks you to join in.
I haven't played too much with the setting mainly because I do enjoy each leader's distinct personality. Meeting up with Tokugawa and finding him all to ready to open his borders and trade techs was disappointing and disconcerting--a bit like a Civ version of the Invasion of the Body-Snatchers, or Stepford Wives. Nevertheless, I think it does even the playing field with the AI to an extent. As I go on and get better at this game, I may start using it more often.