Necropolis and Demon.

The balance is fine; you just need to counter the opposing side's abilities with your own, and with gating focused on Necromancy, the chances will become more equal. Without gating, it's not even worth fighting in the final stage.
P.S. I can't understand why everyone buffs the "Attack" skill for their races. Overly strengthening one side leads to the weakness of the other. Isn't that true?