These are some more good quality KDE 4.8.0 themes I have discovered.
These themes are easily installed with the system settings menu, just sort by rating and the themes list will be displayed. I gave Unity a fair trial yesterday with all of the latest updates and it was quite unstable. As Linus Torvalds said, just use KDE. The Unity desktop environment is getting more configuration tools, but is going down the same road that Gnome 3 is, needing separate utilities that have to be installed to configure something that should be configurable in the control panel. KDE is at least properly configurable and can install new themes far more easily than the horribly unstable Unity interface. You can even configure KDE to look a little like Gnome 2. That is what I have done, I set up my desktop with the narrow top and bottom panels and it looks very good too. This is why KDE will win over Unity in the desktop stakes. The kde-look website is very popular and there are many more themes for KDE than there are for Unity, that is for sure. There are even more quality KDE themes here: http://kde-look.org/index.php?xcontentmode=9 you will definitely find something interesting on this page to improve the look of your desktop and some useful Plasmoids to improve the efficiency of your day to day operations.