Ok, since they showed that faeries can be turned into vampires, is it possible for maenads as well? I know that the wiki lists them as being incapable of turning, but that's not confirmed for sure.
Imo, such a hybrid would be almost like The Originals' Klaus Mikaelson. Unkillable except under special circumstances, and with a venom lethal to vampires(its poisonours vampirized blood wouldn't wear off just like faerire-vampire blood doesn't wear off). I am also willing to bet that the combined vampire and maenad mind control abilities will give it the edge over regular vampires as well.
Add considerable age to that, and we have an immensely powerful creature.