To keep trading fair exotics should [b]not[/b] be tradable. They should be earned on your own, whether it was a random drop, bounty or a purchase from Xur. Also, legendary gear can only be swapped with legendary gear, rare for rare and uncommon for uncommon. There's really no point in being able to trade common weapons. Furthermore, I don't think players should be able to trade uncommon gear upon reaching level 20. Being able to trade will help out many players, particularly players who dislike pvp or pve. I like both but I play way more pvp than pve, I only do the weeklies and attempt the VoG occasionally. Therefore, my vanguard is lvl 1 and don't have enough marks to purchase weapons anyway. However, if trading was enabled I could get in touch with a guardian who doesn't like pvp so I cold play crucible to get him a weapon from the crucible or factions while he can get me a certain weapon from the vanguard.