1) Take that Earthening Rod off your VL. Your vampire's main defense is how deadly he is in combat, and you're FAR more likely to lose him by him whiffing in combat and dying to SCR than you are to a miscast. Ogre Blade is a FAR, FAR better use of those points.
If you're really concerned about miscasting then you should strip the level 4 off onto a dedicated caster instead.
2) Give the hero vampire level 2, so that at least he can bring back a decent quantity of knights with Invocation in a pinch. With level 1 you can 1-die 6" invocation with 50-50 odds of getting it off. The extra spell also gives you more additional flexibility.
...though on the point of secondary casters, where the heck is your dispel scroll? That's a must-have in any list. Give that boy a dispel scroll, and maybe the dawnstone to make up for his ridiculous fragility at T4 2W.
3) I like the core. Excessively large units, which don't need any magic support to be great tarpits. Have fun painting those, though
4) Black Knights: Give them the movement banner. It's cheap and totally worth it for what you're trying to get them to do. Also that unit NEEDS a champion to take challenges, and leave your vampires open to wreck face.
5) I'm not so sure about the grave guard in this list. Your general is going to want to be charging off ahead, leaving your GG behind. That's an awful lot of points to abandon to M4 no marching.
6) Varghulfs...meh. What do these bring to your lists? I'd rather have vargheists or terrorgheists. Varghulfs are cool but they don't really have a role that isn't filled better by something else. Vargheists output S5 attacks but with more mobility. Terrorgheists are a better rare choice, and combat armour. And if you need a hammer then Crypt Horrors are T5 as well, also have regen, and are raised much more easily with magic.