This is how I believe the Marvel Cinematic Universe should play out over the next few years following the Avengers in 2012.
2013
Iron Man 3 (2013) - Villian: Mandarin w/ Fin Fang Foom Delve a little more into Demon in a Bottle. Mandarin also presents an oppurtunity to reference Doctor Strange. But not to many references like Iron Man 2.
Thor 2 (2013) - Villian(s): Enchantress and the Executioner. It was reported that the sequel may stay in Asgard more, but hopefully not too much as there are many other realms to explore. Then possibly, at the end, be it the ACS or just the end of the film, but reveal the Enchantress speaking with someone about how Thor took her down and have this person be Loki.
Doctor Strange (2013) - Villain: Mordo trying to summon Dormammu. I would say the storyline could almost mirror the animated film well, just dont ever fully show Dormammu just hint at it and hint at it. The ACS could then be just that showing Dormammu finally.
Ant-Man (2014) - Villain: A.I.M./MODOK This is hard for me to come up with as I don't know as much about Ant-Man as the others, but I'll try. Have Pym create the particles with his GF Janet. He tests them, they allow him to grow and shrink. AIM wants them as a weapon and raid Pym's place to take it. Pym goes after them to there HQ (an abandoned HYDRA location would be a good easter egg).
Pym fights off many AIM agents but can't handle MODOK that is where Janet comes to save the day. They then destroy the remaining particles. ACS: Ultron!
Captain America: Winter Soldier (2014) - Villian: Winter Soldier/Russians Have it set in modern times with flashbacks to Bucky after "death". He can be the main villain the entire movie until he finally captures Cap and the Russians begin to beat up on him he then remembers everything from before he was brainwashed and helps Cap escape.
Black Panther (2014) - Villain: Klaw After the death of his father, Klaw and his men begin to take over Wakanda for its Vibranium. T'Challa is exiled for his failure to protect the country he rules. He then studies in the UK and US for a while until he hears of trouble in Wakanda and goes back to help. Upon him helping defeat Klaw he is renamed king and all is well.
The Avengers 2 (2015) - Add Ant Man, Wasp, Black Panther and possibly Doctor Strange and Vision. Have Ultron be the villain after being teased in Ant Man, but let him start out good and build Vision.
Then there will be more after that but that can be in Part 2