Board Thread:Questions and Answers/@comment-24174049-20131117220811/@comment-4651179-20131120022641

No. Hulk and Widow need certain development, but not "serious" development. Iron Man had his character development in one movie, the first one. The rest of his evolution is not part of his primary character development. And technically Thor did finish his character arc in his first movie, still pretty rushed, if only humans could also change behaviour in a single week-end.

Also, not every character needs a character development, just the ability to establish themselves. All of the previous Avengers did so, except Hawkeye.