i think zlatan shows his class on the pitch all the time, his efficiency is yet to be improved, but what he does with the ball, combined with his vision is pure class imo. his behaviour of the pitch is not that important imo, therefore i think zlatan is already a world class player.
how do you reckon a troublemaker can't be worldclass? some of greatest players of all time were in fact troublemakers on the pitch. temperament is not such a bad thing, it drives a player more, sure when it gets out of hand it's bad, but temperamental players are one of the best players ever to be seen. just a few names come to mind; keane, stoichkov, romario even totti. all of those players were temperamental and trouble-makers. and all of them were world class.