I am a bit torn on the whole Hunger thing. Yes, you essentially become a Wendigo, but you aren't one entirely. It's the same reason why Lily doesn't have to consume the life essence of people to survive/keep her human form. You are the creature but not entirely to the point where you have every single characteristic of it. You're still human, or parts of you are, so you shouldn't have all the traits that come with it. (Gregory, for example, isn't a slow-moving guy that spends decades deciding whether or not to move his finger a few centimetres, like most Earth/Rock elementals are wont to do). 

Then there's also the matter of him killing his own family. I mean... what the hell is that guy made of to be [i]completely[/i] unfazed by slaughtering his own family? No matter what kind of person you are, you're bound to bear some mental scars from that. Correct me if I'm wrong, but I get the feeling that this guy is there pretty much for "the sake of being evil" or "Antagonistic for the sake of being antagonistic". Don't get me wrong, I'm not trying to insult you nor insinuate that what I wrote is fact, only that it's what I feel. He's a bit too much Wendigo compared to how much Human he should be. 

I can't really name any specifics, but try to perhaps tone it down a little, and see where that leads you. I would also like to stress that this specifically is more of a suggestion, and not a base for rejection. The reason he's not accepted yet is what I wrote above.