My biggest complaint about AOU was that Ultron isn't scary enough. He had the power to travel through the internet and his final form is nearly indestructible! I was hoping for the movie to have Ultron survive to fight another day instead of killing him off. Reach into your back-catalog Marvel! The Leader, MODOK, Surtur, Enchantress! Zemo and Crossbones are a step in the right direction, complex characters with real motivation.