Please, no ELO. It doesn't take long to figure out when you're outmatched.
I think it discourages "gay" play [although citation needed on that], because people aren't obsessed over their score. MGE isn't about winning, it's about getting better (to most), and anyone can get better by playing people that are far better than they are. If someone feels like it's SO mismatched that they aren't having fun or learning anything, they'll realize it pretty quick and find a new matchup.
And obviously, thanks and love to iT.