I haven't looked at the Witch class yet. What you're saying about its complexity reminds me of the Alchemist class— which I've only skimmed. But as I did so my thoughts were, "This is an accident waiting to happen," and, "This is a sop to munchkins who only enjoy the game as absurd, escapist humor."

I could see using that as an NPC class. It's fun to have a contact you visit occasionally who's weird, dangerous, and— on a 1d6 roll of "6"— wondrous. But to have that person in the party in every interaction and combat? Please, no.