Include skins and a color picker so that users can change the look of the GUI to suit their desktops.

I'm sure many users aren't bothered what the GUI looks like, but that said, a lot will care. i like my desltop and programs to look good and if possible blend in together. It would be really cool if you could include extra skins that change the appearance of the GUI, maybe even with the available tools presented in different ways fopr example tabbed tools.