How many teams?
I am not sure you messed up as much as you think. Your top two at RB / WR are find and your potential at WR looks pretty good. Your RBs look to be a bit of a mess, but not in potential. Just in weekly starts. Coleman / L Murry / Gore might be in bigger positions than we think and if the guy in front goes down for any time, you have an instant starter. Ivory is a sneaky get in the event Shady does not play.
Unless you can get someone who is going to see the field more, I am not sure who you would go for. Maybe package Murray and Coleman to go for someone with upside on the WR front. I think it is harder for people to evaluate cross-position so you might get more value there. Then use the same approach with two WRs to find that more solid RB.
I am not saying you should do that, as I do think your team is perhaps better than you are evaluating. I am offering a way to maybe get more value for the players in a trade. Same position is trickier to upgrade.
I would even consider waiting to see how things shape up. It is possible that you have enough depth as you are likely only looking at FLEX with any concern. But you easily have 2 FLEX players from either position as it stands.
I hope any of this helps!