Another thing too, an average ork is smaller than a space marine. If you make a smaller model that just slowly grows based on XP then it's completely logical to have a high level ork grow larger in size to be maybe 8-10 feet, or at least be a foot taller than the largest player model. If this has to be a static scale then you could do it. Otherwise haveing a rage meter on all of the players would probably be the best. The more baddass you play, the more badass the ork becomes. Having this on-top of a static size increase for non-free to play members based on XP would be sooooooooooo sick. Kind of a throw back to WAR online , choppin time boyz