I credit that to Joss Whedon who masterfully managed to strike a balance despite some obvious (perhaps studio influenced?) pandering to Iron Man. e.g. Thor vs. Iron Man (cleverly written to not make Iron Man look bad) and building an Iron Man/Cap plotline which provides some good drama with Steve Rogers but Iron Man still saves the day proving he would lay it on the line. I love The Avengers. It's my favorite CBM ever. But I think Iron Man got a lot of focus. Of course he was the biggest money maker coming into it but Thor was the second biggest. Hopefully other heroes get a chance to shine more in the sequel (and I mean Cap and Thor not Black Widow).