Are you planning to save WAVES OF THE UNDEAD for the Lurkers, or have you dropped that idea?
Looks pretty good here, though it'll be tough to gauge their full potential until the other Zombies come along.
I will also just be using Classic Zombies, but I think one of the Horrorclix figures would be the best way to go.
The Shambling, Hardhat and Cop look best to me for the Walkers.