I didn't see any dispel or mind control skills. O_o
Weakening is unnecessary; it just wastes mana. Storm Arrows are very useful, and lightning helped me a lot in the mission where Anastasia explores her memories, especially when I was completing the quest for the liches. There are Dark elements guarding one area, and the ghosts can't attack them. But that's a matter of taste.
What's the point of teleport if you're defending? It's not very useful for the undead: vampires, ghouls, and lamassu are fast, and the rest are ranged attackers. At most, it can be used to throw spellcasters.
Always use Sacrifice on upgraded vampires and then use them to defend.
There's no strategy here. X_X
With your magic power of 75, the explosion should deal even more damage.

Барон "Vampires"
Отдай свои прошлые сны,
В сомненьях себя обрети,
В бешеном танце душа кружится!
Не думай, что будет потом,
Здесь и сейчас мы живем,
Стань хоть на миг сам собой, слышишь!