No for one reason. This is a restrictive system. If there is to be trading, it needs to be a completely unrestricted system where you can trade anything for anything, and quality or progress of the item isn't lost. That way there is an economy for items, where items with progress devoted to it are worth more. I don't get the gist with the whole quality for quality sillyness. If I want to buy an exotic for 100 strange coins / 100 motes, then I should be allowed to. If I want to trade my fatebringer for someone's thunderlord, then I should also be allowed to. Revise your post, and you'll have my support.