Very cool idea! I almost wish rotes had been around right in the core game. I'm curious, though, why did you go with the name "The Hex"? Just wondering, because it seems as though, aside from "Sympathetic Tokens", they don't have a huge focus on cursing people as such.
I think it would be neat if they had a move or two directly relating to how they'll go to terrible lengths to attain power, rather than representing the powers themselves--you know, making bad deals, using forbidden tomes, etc. Here's one idea I had; feel free to use it if you like:
-Deal with the Devil: When you go to the Monster (or something even worse) seeking a way to expand your power, it will give you a small taste and show you what horrifying, dehumanizing thing you need to do to make it permanent. Do it and it's yours (The Keeper will detail, including profile or custom move if necessary).