Add a feature that if the opponent leaves a battle and doesn't respond for a period of time (an hour, maybe), you receive a win and the battle ends.
I would really like this because frequently when I battle and I am winning, people just leave and don't forfeit, and I can't finish and win. However, I don't want people who lose connection during the battle to lose, so that's why it should have a set period to get back into the battle.