I was just thinking this as well. Considering that she has 0% chance of becoming Regent now even if the secularists install 3 supporting Consuls (which honestly is what I thought her next move would be) her only options are to either 1) rescind her claims, 2) schism, or 3) perpetually rant, rave and otherwise troll every letter from an Elder, claiming that she has "removed them from office".
Unfortunately for everyone on the full members channel I suspect she'll go with 3, though I suppose 2 is an option once she gets bored.
People can put her on ignore, which could take care of option 3.
Other than that, the Elders can't remove from her the options to stir the peasants or auto da fe. However, doesn't that make sense? If someone comes in an illiterate village dressed as a SA priest and speak of the Bloodstars in a semi-cogent fashion, the peasants will just assume she's the real thing.
Realms can order her arrest. You can arrest all priests of realms you are at war with, even if they are of your own religion. Her own realm could ban her if they were so inclined (I don't think they are, but that's valid IC play).
I agree that a mechanism to boot a priest would be nice to have. However the situation is not so hopeless right now. There are things that all sides can do, if they're willing to do it.
