As a playtester, I can tell you the top-level vampires (and werewolves) are tough, but not unbeatable. As others mentioned, ganging up and holy men are key. As a Hammer film fan, it seems entirely appropriate to me.
You can always tweak a stat or two, but I'd advise playing a few games first. We played the heck out of this and, while we're not perfect, I think we got things pretty close.
Aaron