I've been working on the maenad transformation since last night, too, and have run into some enormous issue with crashing during worldgen. I know it's a problem to do with the transformation effect specifically, as if I switch the transformation effect with some other nonsense effect (husk effect or vampire effect in this case) whilst leaving everything else about the interaction like it's targeting and source instructions it goes fine.
I'm currently trying to figure out exactly what the issue with the transformations is. If I fail, I can either do a more basic raving lunatic effect instead of transforming them into a raving lunatic, or I can treat it like they learn a new power that lets them transform into a raving lunatic at will (like "Give in to Intoxication"), and then make the AI use it as soon as they can, which should result in them getting down to boogy as soon as you load their area of the map. Players that catch such a curse wouldn't be obligated to transform though, because the power would have to be willingly triggered, but perhaps I can play with that part of it in some manner as well.
I tried giving the creature they transform into an effect to make them raise the dead as a ridiculously weak steam-based phantom, and that appeared to work alright. Haven't found any maenads in-game yet though so I can't say how exactly it will pan out, but in the arena it works out. Dionysus apparently also was associated with communicating with and feeding the dead, so I figured a phantom of some sort would be okay without stepping into Hades' spheres too far, and I wanted to see if by making the curse also a secret you could learn that offered a raise dead effect they would also build towers like necromancers.
That phantom definition will work for anyone else that employs it as well, I think. Weirdest thing is they like to leave chunks of themselves behind, as "__'s lower arm steam" or whatever. Good news is after being put down once, the corpse ceases to exist (it kinda just explodes, launching steamy bits everywhere) and despite distracting and terrifying the living they can't cause permanent harm. Bad news is you can't bury a corpse that no longer exists, and sometimes slabbing them is impossible due to some bug or other. Regardless of whether you let me keep that in, I obviously need some practice with interactions...
Don't worry; there are far more badass things Hades could do than raise a ghost that can't really do anything before it dies. Like raise zombies that bring plague and fire to the living, or transform into lesser demons instead of sucky ghosts, or huskify the occasional living.