So when are they going to have a real villain to give the Avenger's a run for their collective money?
The only one is Thanos,and they are shitting away a good opportunity,unless they are saving him for The Avengers 2.
I'm assuming that Loki is going to take control of The Hulk,or that Skrulls will be involved in some way,because Loki alone got his ass whooped by Thor,so why would they need a whole team to take him down when it only took one person before?
Thanos+Infinity Gauntlet is the only way to go.
Of course you would have to really tone down the power of the gauntlet,but that's what they should do.