Well, just remember that this is *your* UI and you don't need to accept any advice.
As long as you have a personal reason for having something the way that it is, even if it's just that you "like it that way", then keep it.
One suggestion for opening up your screen some, though, is to use a viewport so that the game world isn't "covered up" by your art panels.
Phanx does have some good suggestions, though. So even with my statement above about keeping things even if you just "like it that way", do still think about whether you *need* it that way.
Art, though, doesn't need to go if you feel that it makes your game more enjoyable.