Sounds like an easy way to prevent griefing would be to make a single elder who's not a priest auto demote out of the elder rank forcing the promotion of a priest.
I'm not a coder. I have no idea how easy or hard that is to code. What I do know is that there is already at least a few things on the list to do. Already on that list is a revamp to religions. I feel confident to say that when religions are revamped that things of this nature will get looked into.
