No, it wouldn't work. I've been playing this game for a few months now and have multiple exotics/ legendaries. Say a friend of mine picks up the game tomorrow, and levels his character to 20 in about two days. With a trade system, I would be able to give him a couple exotics and legendaries to get him to 31. He is now level 31 and has weapons such as, Icebreaker, last word, Gjallarhorn, suros, ect. He just beat the game in two days. Now what is there to do? Raid? That's about it. Trading has a similar effect of cheat codes. Infinite money/ max level/ best item/ character. Sure it's fun for the day or so, but then there is nothing left to do. TL;DR Trading would ruin the game's experience. Remember when you got your first exotic? Or how about waiting for Xur on Friday hoping that he sells patience and time -- and he does. Though RNG is flawed, you still jumped up when Atheon dropped mythoclast for the first time or the raid piece that you needed to get to 30.