My dream job has always been directing, producing, and casting movies. Superhero movies especially. I know that a few of these castings will not be popular, but stick with me! Enjoy!
Dominic Cooper as Iron Man
He already has experience in Marvel movies as Tony's father Howard, and he did a fantastic job... But I would much rather see him as Tony Stark, not his father. He can play an arrogant character really well, and as we all know Tony is a very arrogant man. He is also much younger than RDJ so he would be able to play the role for a little while.
Dominic Cooper as Tony Stark
Channing Tatum as Captain America
Here's one of those unpopular castings I was talking about.
I know a lot of people (guys) don't like him because he is a "pretty boy", but I think he has the skill to play someone like Steve Rogers.
He has experience in action movies such as, White House Down, G.I. Joe, and Fighting... So a movie of this genre would be familiar to him.
Channing Tatum as Steve Rogers
Alexander Skarsgård as Thor
Alexander has the Asgardian physique as well as looks. He also has experience playing a warrior type character in the show True Blood, and he has action experience in the movie Battleship. He was ALSO cast as Tarzan recently so he will once again be playing a brutish character. So he is well-qualified to take on the role of the God of Thunder.
Alexander Skarsgård as Thor Odinson
Cillian Murphy as The Hulk
Cillian Murphy is a thin man who is great when it comes to playing a genius. You may be familiar with him as Scarecrow in the Dark Knight trilogy or Jim in 28 Days Later. He is a extremely talented actor who I think could play the unstable character of Bruce Banner.
Cillian Murphy as Bruce Banner
Imogen Poots as Black Widow
Imogen Poots is no stranger to action movies such as Need for Speed and 28 Weeks Later. She is athletic, flexible, and attractive just like the Black Widow we know and love! I think she would be a great addition to an Avengers movie.
She even resembles Black Widow!
Imogen Poots as Natalia Romanova
Chris Pine as Hawkeye
Chris Pine is definitely well-acquainted with the action and comedy movie genres, he has been in movies such as... Star Trek 1&2 (And 3 which hasn't started filming yet), Horrible Bosses 2, Jack Ryan: Shadow Recruit, This Means War, Into The Woods, and so many other great movies! I think he could easily pull off the role of the sharp shooter we have come to love.
Chris Pine as Clinton Barton
Brad Pitt as Nick Fury (Earth-616)
Brad Pitt has an arsenal of movies behind him to prove that he is more than capable of playing this role. He has proven more that enough times that he has mastered the art of action movies, from Ocean's Eleven to his newest movie Fury. He, out of all actors, is Nicholas J. Fury.
Here is a side by side for comparison:
Brad Pitt as Nick Fury
Sam Claflin as Spider-Man
Claflin has experience playing fantasy roles thanks to Snow White and The Huntsman, Pirates of the Caribbean: On Stranger Tides, and The Hunger Games. Since his first appearance Pirates of the Caribbean he has been a rising star and I think he would absolutely AMAZING in the role of Peter Parker.