Those of us who've suggested punishing the problematic players have ideas on punishments, but I haven't seen anyone suggest an idea for a reward system. The commendations aren't worth it since, for me, I've already maxed out my commendation achievements. If we were to get a prize for every game we played, we'd run out of prizes after a day of playing.
We don't need an incentive to stay for the whole round, playing the game itself is incentive enough.
When a captain on your team leaves, EVERYONE ELSE in that team gets punished, but the quiter gets to go play another game like a clean slate.
If you want to reward someone, reward the people that were abandoned, because they're more or less screwed for that match. Sure it's possible to still win, but highly unlikely.
It is infuriating for us who get bent over like that. I, as a captain, will try to still play, but after getting killed a couple of times without even being able to take down an opponent's armor, I give up. I tell my engineers to stop repairing, my gunners to sit back, I press the surrender button, and fly into the middle of the other team while posting "Kill us" in match chat.
If you don't punish the deserters, then the rest of us suffer. Why should we be the ones who get the raw end of the deal?