Hi,
I redesigned the back-end a little bit, and tried to give it the same look and feel as a Windows app. It doesn't look that bad, I think:
Maybe somebody wants to use it. Download the file, and put it all in your pivot folder. Make sure you make a backup of the 'templates_pivot' directory before you do this, because it will have to be replaced by these files.
And yes, as soon as you upgrade to a newer version, changes will be lost, so be careful there as well.
Of course it would be nice (request alert) to have the possibility to change the theme of the back-end.
Edit: Although I know better not to do it, I just opened the back-end with this lay-out in IE7, and guess what: the top menu looks like a five year old made the images. Still workable, but ugly. I don't feel like changing it though, so for all you IE users: stay away from this, or deal with the uglyness