race-bending and the Marvel movie universe

I'm currently writing an Avengers series set in the Marvel movie-verse called Responsible Science, and I'm posting the fifth story, which is called Let's Stop The Time Warp (Again). In this story, I've included several Marvel characters whom we haven't seen in the Marvel movies. Since actors haven't been cast for these roles, I feel like some liberties can be taken with canon--yes, they're in the comics, but it's not like Mark Ruffalo looks exactly like comics!Bruce Banner; Gwenyth Paltrow doesn't look exactly like comics!Pepper, and so on. These characters don't even necessarily have the same backgrounds they do in canon. I thought since the Marvel movie-verse is an AU anyway, it'd be acceptable to race-bend some of the parts.

I'm kind of upset with some aspects of the current reboot trend, since it allows creators/producers/Powers That Be a built-in "excuse" to cast lots of white males, since that's what a lot of older western canons feature. I'm not going to go into a long diatribe about it; I wrote an essay here. I will say that I think it's a damn shame that so many aspects of a canon can be updated or changed--time periods, plots, characterizations--but as soon as you suggest changing something like gender or race or sexual orientation, you get a lot of people saying, "But the original isn't like that!" A lot of these originals were produced by white males in conservative eras. I'd like to think that we've come along way since the forties, even since the eighties; I'd like to see those changes reflected in my media.

( Regarding Marvel specifically )