Make a ranking for nice players
People who are a positive part of the community should be marked. I think that when a player is positiv and team oriented it is as important as his/her skill level. Maybe make a badge in the corner of the loading screen in the same colours as the ranked symbols. Players with the most honors and least reports (which triggered a punishmend) should get a challenger badge, and then the way down. Would maybe stop at plat or gold. So that it is not possible to decide if someone is an occasional flamer or a really toxic person so that noone gets stigmatized too much.
Edit: The match-making should not be influenced by the honor ranking. It is just additionally so that you can easier add people, and to motivate people to treat other nicely or as a reward for those who did