I like the Arc-Zenburn theme. However, I find the blue color a bit out-of-place on Ubuntu. So I have modified it to give it orange items. This was designed with Compiz in mind and works in Xfce (but not Xfwm4) and Ubuntu's Unity. It has not been tested on GNOME Shell.

None of this is my personal work. I just took two themes and put them together into one. Credit goes to the following:

Arc-Zenburn: https://www.gnome-look.org/p/1258800/
Arc Orange: https://www.gnome-look.org/p/1013425/