6. James Rhodes
One of the few truly hokey elements of The Avengers was the absence of major characters from within the MCU, namely James Rhodes aka War Machine, who built himself up as an awesome badass in Iron Man 2, only to be entirely absent during the Battle of New York. Though Marvel have released some comics to fill in the gaps - stating that Rhodes was away on his own mission during the battle - it's just a bit lazy, and hopefully given the flak they got for it the first time around, Rhodes will be brought into the fold for The Avengers 2, presumably as Iron Patriot. Rhodes is a likable character yet, given that he's not an Avenger, he can be killed off without p*ssing too many people off (other than the dedicated Marvel fanboys). Though it'd be a shame to see an actor of Don Cheadle's caliber exit the franchise, he could get a heroic, epic death worthy of himself and the character. The main question mark, though, is whether he will actually appear in The Avengers 2 at all.
Chance Of It Happening: 4/10