Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
In any given week, I am likely to use two or three Linux desktop environments. Partly, I switch so often to keep up to date. But the main reason is that, whatever environment I am using, I soon become aware of its shortcomings and start thinking of another's advantages.
Clearly, the only Linux desktop with which I am likely to be completely satisfied would be one I built for myself. However, since I am unlikely to do that any time soon -- or at all -- I can only continue to switch regularly, repelled by a feature in one desktop and attracted by a feature in another, like a piece of iron between constantly shifting magnetic fields.
Meanwhile, here are the best and worst features that I keep noticing in each of the six major desktop environments for Linux: