because it's just more to have to deal with, remember someone has to keep all this stuff up and running in timely fashion. also match making could suffer with more maps, think how long it takes right now, sometimes, to get a full fireteam. I don't know about you but I've gotten thrown into some 4 on 6's immediately. same with strike matchmaking. I've literally been the only one in the strike and have done most of them nearly solo. More elements. more problems is my logic.