How is trading game-breaking? If all the game wants to drop me are a few specific items due to the weird RNG algorithms working against me, trading would correct that. The game has seriously given me 4 Invectives. Literally every Exotic Special Weapon engram I've gotten has turned into Invective. But I know people who can't get Invective to drop to save their life. Trading would bridge that gap. A simple fix to keep it from being a source of boosting would be to make it so you could only trade weapons of the same rarity and year to other players. Exotics can only be traded for exotics, legendaries for legendaries, etc.