Re: Characters you'd like to see in future Avengers movies?
Maybe Avengers 2 will be the Captives of the Collector storyline (which was part of the Korvac saga). Perhaps they're all "assembled" (including other characters who haven't officially joined the team) because of the Collector (who is seemingly in the Guardians movie), and not via Fury this time.
That certainly would give Hawkeye a bigger role if they went with that storyline, since
he's the one who took down the Collector in the end and rescued all the Avengers.
And of course, the Collector would lead into another big villain - Korvac, who is strongly associated with both the Guardians and the Avengers.
Anne Hathaway: "You did not just ask me that!! What a forward young man you are!!! My goodness!!"