I enjoyed the movie. Yes, the changes in the backstories of the characters did bother me a little, since I was a big fan of the comic. However, you would have to change some things.

For instance, in the comic both Snake Eyes and Storm Shadow were Vietnam vets. That would mean they would have to be at least in their fifties, and probably sixties, if you kept that the same. And besides, it's not like they don't change backstories for all the comic adaptations (XMen is a good example).

The uniform thing didn't bother me at all, since wearing all the different uniforms in a tactical environment never made sense anyway.

I do have to say that Sienna miller did pull off the Baroness uniform well.