I agree, you'd think they'd conduct usability tests BEFORE making the choice to switch to Unity. It seems that Ubuntu makes UI changes for the sake of being different, not better. Like moving all the window controls to the left side of the title bar in the current release of Ubuntu. Why?

Agreed, and the same thing happened, I believe, in Gnome 3. They did usability testing, but only AFTER the features were essentially frozen. Instead of using users as a guide for what to develop, they used them as a confirmation that what was already written in stone was good or bad. That's just not good practice.