Hey, Wastri rocks!
Anyway... I voted for Orcus, Vecna and Strahd. Orcus because he's the classic demon prince, Vecna because he's the Lord of Secrets and has a great backstory, and Strahd for sheer classy lethality. I am disappointed by the lack of Eberron support, though, because both Vol and the Lord of Blades are great villains.
Demiurge out.