From a company standpoint if people are trading for things they want, then what's the point of grinding for it? Wether or not you've got the weapons you're looking for, you still need to play strikes and raids and crucible to level them up, or just gain user experience. So one way or another you've got to play the same activities you would to get rewarded the item(s) you're looking for. So no, no trading system, it's exciting to get the items from the cold bitch RNG has proven to be.