Carnage is my favorite symbiote and his brutality and viciousness is what I'd want on a team of villains.
Professor Zoom is my speedster. Fast, cunning, and basically unstoppable.
The "Team Leader" is Magneto. He has great leading experience and his power is amazing and makes him a dangerous combatant. (We know there would be no true leader since they all would show who's better.)
Ultron. He just can't be trusted. But he's smart and one badass villain that knows to keep his secret plans Secret.
Atrocitus, leader of the Red Lantern Corps. With just a soul filled of hate, I'm sure he'd deny joining my Crew of Villains since he wouldn't be leading them.