A big problem with making mm fireteams is: what if your buddy gets kicked to orbit or offline? MM could fill their slot and now you have to be that douchey guy who boots someone. With trials, having a reliable, well versed team makes for flawless wins. You can't always rely on joe blow to have a mic or even know what's going on. Best bet is to get on lfg, meet some new people and enjoy. This game is quite boring without a fireteam. My friends and I are always partied up even if we aren't playing the same games. This game was meant to be a social event. Hence big a partial MMO. Why have all those people online if you're not going to talk to one of them?