It's not entirely clear how terrible things are for the monkey's paw situation. I can imagine it being a dispute about appropriate use of Miraculous that got out of hand, but I'm not completely sold on the idea that Hawk Moth is completely without compassion. I would believe in a heartbeat that Peacock would try to stop Hawk Moth if Hawk Moth attempted to akumatize Peacock or Peacock's family, though. And that could have created a loyalty conflict that did not end well for anyone.

I think the snake wielder is someone whose personality traits would get them sorted into Slytherin, being ambitious, competitive, and interested in art forms that are usually transgressive when found in the wild. You might be thinking of them as more dragon-appropriate, and I wouldn't say no to that, but if I were going to give out a dragon Miraculous, I'd give it to someone who is fire-breathingly protective of the things (or people) in their care.

Clear as mud?