If I have to choose I'd say the vampires. LKHs vampires are incredibly powerful and so very diverse.
I don't dislike the lycanthropes, in fact I generally like them. Richard annoys me but the rest of the wolves seem normal, and very real. I like them. I like Raphael, the Rat King a great deal for his loyalty and quiet strength. The wereleopards are impossible for me not to like, with their insecurity and fragility. But the vampires have JC and Asher. They have powers of the mind. They have enormous strength, and they still have a great deal of personality and individualism.