ever thought of making your buddy fight back???
I think that would be cool to have. It would be an option that you could turn on and off. have him throw things back at you or try to beat up your cursor.
Another cool option could be like a buddy battle arena. Set it up so that two buddies are in the same window and they pummel the crap out of each other.(kindof like a rpg build up process w/ stats and skills that you can buy or upgrade w/ experience.)