Doesn't AtE-CK2 have an event chain surrounding a so-called 'Westphalian Treatise' where the Emperor gets to put a Luther-esque monk on trial and various HCC nobles get to convert to his (Charismatic? I think) faith? I
We've been taking that as a reason not to do a reformation in the HCC, since as you said something like that already happens in AtE.
maybe Piety would be better for consumerists? Not sure what it would represent, or what its buffs/debuffs would be for (im)piety, though.
Unfortunately the piety mechanic can only be localised to one religion at a time, and we'd like to keep it for the Muslims.