I usually go out of the way to help anyone I see in the area I'm grinding. This includes buffing and keeping an eye on them to see if they get in trouble. Liberal heals and even inviting them to the group if I'm not 5boxing seems to help too. I also try not to destroy all the mobs in an area, as there is nothing worse them trying to fight for quest mobs with a boxer.

I'm not sure if this has kept me from getting reported, but in the 2 years or so I've never had a GM approach me.