Since I'm playing Superman, I want to chime in.

I didn't really get a chance to weigh in on Kara being part of the GotG, because I was distracted by IRL stuff and was never actually contacted about it. I'd honestly prefer to have a Supergirl that I can interact with in Metropolis. 

However, since Guardians Kara has already been accepted and it would be a dick move to retroactively say "actually I'd rather not," the nature of my take on Krypton does allow for multiple possible futures, and thus multiple possible Kryptons. So we could have a Metropolis Kara and a Guardians Kara and it shouldn't be a problem, at least not for me.