So, I actually have this feat and as I understand its fairly new. So perhaps a bit of feedback on its implementation.
Becoming a cannibal doesn't generally mean you can never manage on other foods, it just means that generally its your preferred. So the implementation becomes in question as to what IC reason does eating normal foods no longer have a "food" benefit? I can rationalize the healing part, but to have your char sit 24/7 at literally starving because cannibal is a bit...strange to say the least. The rest of what it does and costs, I love and can understand, but can we please put back gaining nutrition from it? It really just makes no sense otherwise, cannibalism is a choice lifestyle, unless there is some very strong reason that all of a sudden, you can magically no longer gain nutrients from everything else like a werewolf?