Zombies individually was the hands down winner for this poll. So that's the end of that.
The next poll is about which side the Engineer should be part of. Here are the two possible Engineer configurations.
Survivor Engineer: As a normal engineer but can build only level 1 sentries. A sentry requires 130 worth of metal to fully reload and runs out of ammo after shooting 450 damage worth of ammo. Also has access to teleports, but not to dispensers.
Zombie Engineer: Equipped with only a melee weapon and his ability to create the teleporters. Teleporters require only 5 seconds to charge up to be usable by the next person. Zombie Engineers move at a speed slightly slower than a Zombie Scout.