A new little snippet from another Joss interview, I'm trying to leave the link but it keeps censoring it...
Having such a wide variety of characters, initially Whedon sought focus by telling th story largely from one person's perspective; defrosted WW2 super-soldier Captain America. "That was the plan anyway". However, "In the final cut that's probably not true," Whedon reveals. "There was stuff with Cap I cut out. Although he has an 'in' with the audience in that this world is stranger to him, so he's an identification figure."
The climax Whedon pitched Marvel was so enormous that it was apparent there wouldn't be enough time or money to pull it off, "But that's exactly what we shot," he reveals. The scale is "quite large", but it's not about that. "Its the toll it takes," Whedon says. "I find superhero movies to be a little to [dull?]. And when you have Earth's mightiest heroes - like Thor, you know Thor! - you have to put them in a situation that makes you feel like they're not all going to make it." "The climax of this movie isn't one where you go, 'Oh yes, there's the Avengers, good for them, bye!'" When it all hits, it hits hard."
Whedon then went on to discuss The Avengers potential sequel, essentially revealing that he went all-out to avoid Iron Man 2 syndrome, where the story's reduced to a series of sequel-pointers. "We DO give a nod to a greater problem than the one solved in this film." says Whedon. "I'm a great believer in the idea that if you make the first one to be a 'first one,' then you have already failed," asserts Whedon. "As much as we want to service the idea of a film in a franchise, I want this to be a satisfying film experience. I don't want people to go out saying, "When's the next part?" I want people to say, "Oh, I want to see that again!"