Why not just add a negative stat for commends, call it 'condemn' for sake of discussion. Then instead of commeding good players so they party with you again specifically. You could commend them so everyone who has high commends and or zero condemns plays together?
basically if your a troll or hateful person, youll most likely have a lot of condemns and there fore will not get in lobbys with players who have little to no condemns. (new players dont get forced in with the baddies!((Because they start with 0 condemns)))

Recommending could also give rewards as well, so people would not just walk out without even caring.