I like the 3 stages idea that Magdaleena mentioned. I don't know how they would put it in (for the third stage they'd have to create an entirely new model with animations that's controllable by the player) even better would be gradually transforming werewolves that change as the moon changes phases (again, that would be difficult to implement but it would be cool)
I'd also like them to do like they did with vampires where they have a skill system and hierarchy. Maybe the top level would be Alpha Werewolf? Also a way to customize the werewolf form like they did with vampires and their "dark form".
Different skills could be werewolf strength (they don't get tired from working out), wolf sense of smell (easier time getting rare items), part of the pack (easier time with dogs and cats or just dogs maybe since they're related to wolves).
A new thing could maybe be something where their hunger is only filled by meals with meat in them since wolves are carnivores.
