I've been using Linux Mint almost exclusively for the last 10 years. I've always stuck with Cinnamon, it just works for me. I'm not into fiddling around or fancy effects, my computer/desktop environment is a means to an end for me, that is, using my computer for a purpose, not to spend too much time fiddling around with the computer itself or having the desktop get in the way. Mint also has XCFE and and Mate editions, and I suppose there are ways to put the other desktop environments on it too. What say you? What's your favorite Linux Desktop Environment.
Windows responses get the :gamer-gulag:
Gnome when I'm taking depressants. Herbstluftwm when I'm taking stims.
I highly recommend hlwm for anybody who likes i3 but finds its configuration system too constraining. Hlwm does all configuration through IPC, so your configuration file is normally just a bash script, however you can use python or ruby or whatever you want. It also allows your scripts do a lot of introspection of the state of the window manager and its clients.
One trick I like to do is using awk to scrape the Xresources color scheme so the colors can be used directly in various scripts. i3 eventually got this functionality built-in, but that would never be an impediment if you're simply writing bash scripts.