Phase 2 had a disappointing lack of Tom Hiddlestons Loki, who was the best villain of the MCU so far (although thats not a hard contest to win). When we last saw Loki he was impersonating Odin on the throne of Asgard, a plot point that will no doubt be a major issue in Thor: Ragnarok. Aside from that Kevin Feige has confirmed Loki will be a major player in Infinity War too, which sets up the tantalising idea of Loki joining The Avengers. Loki was formerly the owner of an Infinity Stone which he then lost, which almost certainly means Thanos will come looking for him; and hell want more than an apology. This means Loki might have to play nice with his former enemies, and having the God of Mischief working for the greater good would add a lot of spice to the line-up; he's not going to get much love after the whole New York thing. Thats only a theory of course, but it makes sense when thinking through how Loki will fit into the story.
