So, as we all know, Joss Whedon is directing.
And, as many of us know, Joss Whedon has a certain....style. He takes a particular approach to storytelling. Accordingly, here is my first prediction about the film.
Hawkeye will die.
Why? Simple. He'll be one of the most likeable characters, played by a likeable actor (Jeremy Renner).
Ergo, in a Joss Whedon production, HE MUST DIE. Because that's how Joss rolls. I envision it going down something like this:
He and Cap will be strolling around the Avenger's mansion, talking about this or that, when ZZZZZZAAAP! he's fried by a stray power cable. No final words, no meaningful speech, no heroic sacrifice. Just random **** luck. Oh, and it'll happen right after he's found out that Mockingbird thinks he's cute, and he thinks there might be real potential to the relationship. In fact, it may happen right as he's in the middle of saying the word "Relationship."