You're definitely going to want more Vampires. They're great! They're cheap and in my opinion, better summoners than Necromancers. You could get a Vampire with a Dispel Scroll and Dark Acolyte for 155 points. That's a level 2 wizard with the Lore of the Vampires that also allows nearby units to march. That means getting to your enemy faster, and that means winning faster. You could also replace a DS with the always awesome Helm of Commandment. This lets you give one of your squads the WS of the wielder for the rest of that turn. You can imagine the good times. Of course, for what it's worth, Necromancers are still very effective, I just favor Vampires over them.
You may also want to invest in a Corpse Cart or two in place of those Dire Wolves. They are your only fast cavalry in your army, and they will be awfully lonely up there. Corpse Carts will allow everything near them to always strike first, which is amazing against close combat armies, especially those damn High Elves. That is of course, if your enemy does not dispel the Miasma. However, if he does, then that's less dispel dice for him to knock out your other spells, so either way it will work in your favor.
Hope this helped, good luck!
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