1500pts Vampire Counts

I would probably reduce the Grave Guard to 30 models and run them in a 3x10 horde so all can attack, use the saved points to put the Banner of Barrows in there to give them a +1 to hit, in which case I would also swap the Vampire for a Wight King BSB, so he can also benefit from the magic banner. The Wight King is also a little tougher to kill off, which is nice for a BSB.

I'm guessing you are using the Skeletons as a bus for the Necro, but I'd prefer to beef them up a little for combat instead, to 30 and also run them 3x10, or 40 with spears and 4x10. Put the Screaming Banner in there when facing Chaos.

You might have extra points left over from my suggestions, you can put in a Zombie bus for the Necro, 25-30 is good to start and then grow the unit during the game.  But now you are talking quite a bit of models to paint in a month!

Thanks for the suggestions. I'm using the vampire hero mostly because I wanted a vampire in my vampire count army though I did consider a wright king.

I'll look into spirit hosts as well.

You've only got 3 units, none of them with a better movement value than 4. Your magic is going to be reliant on spamming a lot of Vanhel's Danse Macabre if you want to be getting into the match-ups in combat that suit you, and potentially Raise Dead to get some chaff.

I know Tomb Kings are slow, and Warriors of Chaos are perceived as slow (they're not; they have plenty of fast units) but I'd look at your list and think I've got an easy job. 3 big slow, unwieldy blocks (neither the Ghouls nor musician-lacking Skeleton Warriors can quick reform, and the two hordes will struggle around scenery) - I just need to avoid engaging the Grave Guard with anything that matters and look at taking out the Necromancer/Skeleton Warriors block.

Vampire Counts have some of the cheapest chaff units in the game - 40 points for Dire Wolves, who can even Vanguard to reposition. 32 points for a pair of Fell Bats. 45 points for a Spirit Host.

I admire your desire to take a Vampire hero as they're under-utilised and are "fluffy", but they really are poor, and he's pricey at 248 points. Drop him and you could spend 50 points on the Banner of the Barrows (which makes a massive difference to Grave Guard), around 150 on a fast damage-dealer (5-6 Black Knights or 3 Vargheists or 5 Hexwraiths or 1 Varghulf) and still have points spare for a chaff unit.