[Dragar]

I've never had the opportunity to try it yet, only just reaching vampire count point in my first MP game using this strat.

In the late game you'd need a lot of effort to push dominion out quickly, and blood always seems in short supply - to be honest I see the vamps there primarily as an adjunct to your armies for casting Darkness, and secondly as defenders and blood hunters. You have ample flying demobreds and unique demon summons to go on the offensive, and vamps aren't the best with the heavy fire evocs you want to be laying down.

As it is your first couple will probably be remote searching death, and it's worth empowering one with fire to start churning out skulls of fire. At their high cost the only way i see getting heaps of them as possible is if somoene beats you to all of the unique blood summons and vamps and soul contracts are where you pour most of your blood into - I must say a good fall back option.