Nah, but maybe there should be two types of faith managers...the head and the hand. An FM that has to be a priest class, who would be the spiritual authority and general interpreter of the gods will...and the other being the leader who is responsible for ensuring the gods will is set in motion (preferably this would be the favored class, but i could see any working).I guess that leads to the question - should higher ranked faith members be "turned into" priests?
Limiting maximum faith level achievable
A prerequisite for Eliminster getting to where he is today, was sharing a bed with a god. Once you do that, you're pretty much the authority of your religion - regardless of class