Honestly Dr.Voodo is just more useful in many parts of the game with his power control. Although I wish his spirit venom didn't get effected by poison immune champs, his power control still comes handy in those scenarios.
All he has is basic armor and armor break. Give him something like power drain on special attacks. Also Ironman should get an AI that gives him few stacks of armor. The armor can be consumed to give him power and health.