What I think can be done to make the editor more awsome, is if it had a setup for the windows, similar to VForge and other editors - a thin side bar with the window panes. Just slide the mouse over to the side, and the window slides out and stays there until you click somewhere outside, then it slides right back. That would certainly take away the clutter.
I just might try to edit it to do such, but since I don't usually work in xml, and AngelScript is new to me, I might change my mind because of the time involved.
I hope it is being considered by the Urho3D team.
Great job though.