Exactly, get respect by playing enough games. At first it will be tough, as nobody knows you. But as time passes, everybody will get to know your name and know how you play without having to rely on statistics.
I thought about something like "Honor Points". When you finish a game, you can say which players behave correctly and award them an Honor Point. This way players can forge a reputation by playing nicely. I don't see a nice player turning into an ass for no reason, so a player with a lot of HP will always be a good person to play with. Even if they are not that good, they will not quit or rant about everything or insult other players.
Playing a game online is supposed to be fun, and I don't like to see it as a competition. Loosing can be fun if you learn something that makes you better, and is easier to lose if nobody keeps track of it.