Shattered Kingdoms

Jorlian, if you fail to see that you need to get your eyes checked

Charisma depicts how diplomatic or persuasive your character can be.

Seeing a street bum cuss and swear while speaking about his way of life is not probably going to invite a lot of listeners. On the other hand, Some well suited figgure putting down a fluent speech using impressive words would.

I dunno. There's nothing that says a priest needs to be persuasive, enigmatic, or appealing. You can very easily have a priest that sucks at dealing with people, giving speeches, etc. and so on, - the persuasive power of a priest is in the content of his words as provided by the player, and nothing else. Nothing should be automatic about it (as utilizing CHA in the power of the class would imply).

Priests are beautiful as they are, and they're getting buffs as is, so let's not try and screw that up, eh?

Charisma is not all about giving speeches being enigmatic and dealing with people. It also depicts your power of character. As far as stats go, Wisdom is knowing when to use your powers, Inteligence gives you a greater understanding of them, and Charisma makes your connection to your source of power, your god, stronger.