I was just thinking, my main character is an Argonian, do how will the tail fit in as a vampire lord?

I'm guessing the tail just disappears, but we don't really know at this point in time. At least I don't think we know, anyway.

Hmmm... the vampire lords might be a bit awkward for the lizard and cat folk.

Well their tails already seem to shorten in length when they become werewolves, which I imagine is fairly awkward for them as well.