Several high-profile games do this and it tends to work out very well. Look at GTA V, they group all poor sports together so they can only play each other. It's a start and would certainly help. Other than that, a disconnect should be registered as a loss for both players. Yes, it would suck for the innocent person who had nothing to do with it, but I guarantee it would curtail a lot of the crap going on in most fighting games.
A loss for both players? Really? Can you add more incentive for the behavior? This makes no sense at all.
It's bad enough right now that the innocent get a disconnect tally. Right now, the rage quitters have all the incentive in the world to keep griefing by pulling the jack and denying a win and adding disconnect noise to the stats.
I could care less about my win/loss record I just don't to waste my game time with scumbags that behave this way. I would rather spend time losing to honest players and enjoying the match play.
In fact, when I get a couple of wins in a row, I typically switch to a non-main just so the other player gets a better chance at a win. That's how I play and I know others who are like-minded can't stand wasting time with rage quitters.
The one consoling thing the stats do paint is an obvious picture on who the rage quitters are. Simply look at high win rates combined with high disconnect percentages and boom there is your rage quitter scum.
Really the stats that should be visible during the pre-match pop-up is win percentage along with disconnect percentage, the higher each of them are the more likely they are raging.