I don't see anything but a positive effect on both ends if you start allowing players to be able to reset their spar W/L for a fee of something like 5000 gralats. I know a lot of players would do it, which would probably increase daily quest activity and/or the amount of $$$ coming in to the game. There's practically no cons to the situation either, I don't really see how it can be abused. The only reason you'd want to reset your W/L is if you've lost a ridiculous amount of spars and believe you can sustain a better ratio with a clean slate.