Why exactly Clavicus Vile? As far as I got it, they more or less stumbled upon his shrine and begged him to cure them. I can't see how Clavicus Vile is related to vampires or the undead.
Vile is the closest thing to an imp or demon in TES lore.
He likes making pacts with mortals that then do not turn out the way the mortal intended, but still he collects the soul.
It is imaginable that someone became a vampire because Vile promised immortality.
However for someone who knowingly became a vampire,Vaermina, the Prince of dark portents, or Molag Bal, the Prince of [censored] would be more suitable.