I don't have coil exp yet but couldn't they make the system drop 1st randomly decide on the armor slot, example helm armor, then analyze the group so it does not drop a piece that is already equipped by the classes? Like if the two tanks have X tanking helm.. then it skips that as an option for when it decides which helm to drop. This will minimize waste drops and maximize (somewhat) the chance for any given person to get something by possibly skipping gear others dont need.