Maybe Riot can implement a trade system similar to the gifting system where you can ONLY trade with friends. That way you can't get screwed over by other people and if you do get ripped-off by a friend, that's kinda your fault for trusting them and you should probably delete them :). I think it would be cool if you and a friend could go into a trading lobby (similar to a custom game lobby) and see what the other person has (skins, hextech items, summoner icons or even ip) and select what you want and what you're willing to trade. Once both players agree to the trade, there should be another confirmation to ensure the trade and also acknowledge both players about the rp value of the items that they're trading to make sure it's a fair trade.