What I need is performance, eye candy is optional.

My primary desktop environment is Xfce, as it is more lightweight than GNOME, KDE, or Cinnamon (Mate is out of my choice), yet it has more goodies (plugins) than LXDE. But due to my 4-year-old laptop, I found that LXDE has better performance than Xfce significantly. I can run multiple heavy applications at the same time, especially Firefox and Chromium. Xfce performance drops when I run both applications simultaneously. Switching between applications is slower. If running with Skype at the same time, and doing some development testing, the performance drops drastically.