I've found Xfce with Wallis theme to be quite comfortable after I ditched Windows 7. Been using it for 3 years now.

Also I enjoyed how easily I could modify it:

- xfwm4: zoom only to multiples of integer, nearest neighbor only

- xfwm4: stop moving zoomed area after the cursor when Scroll Lock is on

- xfce4-screenshooter: supply custom actions with parameters %x %y %w %h of a selected rectangle, allowing me, for example, to select a rectangle and then launch a screen recording script.

Never found the use for multiple desktops, though.

The only part that irritates me is having to interact with the GTK file chooser (file open dialog). Someday I might be annoyed enough to replace it.