Ok but apart from the wobbly transparent windows, does it ACTUALLY IMPROVE USABILITY? I don't see the point of adding in all the animations, transparencies, etc. if they aren't used to giving you the ability to get your work done with less keystrokes/mouse clicks and to show you more information or show you the info you want in a clearer manner. A good example of my gripe is the window switcher in Unity 7 - it shows window thumbnails (which is useless when you have a dozen black terminals, so you just get a dozen black indistinct rectangles) but doesn't show their names, which is really their only distinguishing feature. If it were built with less shiny graphics, literally as a list of text entries, it would be more useful!
It doesn't matter since they're going to scrap it in 18.04 for Gnome.