2. Thanos
We saw Thanos briefly appear on screen during the credits of the
Avengers movie, where he was shown to be the intergalactic warlord behind Loki and the Chitauri's assault on planet Earth. Having failed on that front, it might be time for Thanos to up the stakes and either recruit some stronger warriors to do his bidding or get his hands dirty himself. Either way, we want to see more of Thanos on screen after having him dangled in front of us like the proverbial carrot. He needs to be powerful too. Having been unveiled as someone capable of of controlling Loki and the Chitauri, it certainly
seems as though he's going to be as powerful as his comic book counterpart, but that needs to become evident. In the comics, Thanos could - quite literally - defeat the Marvel cinematic universe's lineup of Avengers on his own in a physical battle. He is far stronger and far more durable than Thor and Hulk and possesses a wide variety of more esoteric powers, such as telepathy/mind-controlling abilities, energy projection and manipulation, telekinesis, teleportation and matter manipulation abilities. This is a being who took everything that Odin (who can destroy galaxies in the comics) could throw at him and, whilst defeated, was still able to stand and was willing to continue fighting, which gained him Odin's admiration at the very least. So, hopefully Thanos will get plenty of screen time, even if it's just to see him manipulating a new villain/group of villains. Although preferably we will get to see at least a hint of what he's capable of in combat situations.