Original Avengers?

[Savage]

I was watching Iron Man recently and this thought occurred to me (and I'm sure I wasn't the first one this occurred to). Nick Fury proposes to Tony Stark that he is not the only superhero in the world. This is at a point before there is knowledge of Thor's presence, Captain America was still lost to time, and Hulk was most likely considered a menace by SHIELD as well (certainly not a hero anyway).

This got me thinking, should every Marvel movie be an origin movie? I would love to see movies where the heroes are already established and known to the world. I would like to see who exactly Fury had in mind for this Avengers initiative aside from Tony Stark. He pretty much lucked out as fate brought him a pretty awesome group of heroes to manipulate after he decided that Stark was only good as a consultant (which he looked pretty disappointed about in Iron Man 2).

Black Panther is a legacy hero whom I can see being in the cards. What other heroes can you see being pre-established in this universe?