I pretty much exclusively play redside. I did some blue during live, but never really liked it.
One thing for the morality folks, there is a lot of ambiguity on the redside. You may start of doing a bad guy plan and somehow end up with a good guy type outcome. Or maybe the outcome is some weird neutral. There is lots of content like that. OI course, there are still the classic bad guy things like rob bank, defeat hero, destroy stuff.... badges for mowing down civilians, etc.