I vote Minimalist.
In a sentence, after a lot of test, KISS stay the best approach event for "complex" usage like OS GUI.
Historic with desktop OS:
I discover the computer world with a Thomson (TO9+) computer (games, animated cartoon builder and basic...)
I was a Mac OS 6 -> 8 user and left the Apple world to Linux (Yellow Dog Linux, Debian and a lot of "distro" I was comfortable with Xubuntu).
When Apple launched Mac OS X, I saw a real bookmark with "#!/bin/sh on a mac, you bet ?"
And I bet... I was back on Mac (I still use Mac OS X today).
I stop using linux in my desktop (thanks X11 on Mac OS X) and in the same time, I replace Linux by FreeBSD on my servers.
I never had a DOS/Windows computer.
Why OS X stopped to be sexy for me?
This 4 last years, a lot off features that I use every day is remplaced with a golden jail in OS X.
Screens (virtual desktop in grid) is remplaced by virtual desktop in row !
The mixing "fullscreen application" "desktop / window" is a nightmare. You nver know where a new window open, when you want move a window, you need to minimalize it in some case. Why a new mail message open an half fullscreen window aside my browser ? And how the hell I can drag and drop from my desktop to my fullscreen app without touching my keyboard ?
The Mac OS X desktop inherit from iOS usage and the result is against my productivity and my 'liberty'.
What I try and why dwm ?
So, I bought a laptop and decide to use FreeBSD as desktop OS.
I try my old friend (XFCE) but it was not as sexy as I remember.
So I try, Gnome, KDE, Enlightment ... a lot of test, and all is under the OS X quality.
One day, on my OS X, I try to project the OS X futur. And for me Apple try clearly to transform the OS X desktop into a tiling window manager. All things that I dislike is a mix between "finder/window" mode and fullscreen mode.
Finally, I try some WM and I am very comfortable with dwm.
I write a script to launch app from image with sxiv in 20 mins and the result is as good as Apple launcher.
dmenu is a good tool (but I will filter the entries ...) and finally a lot of cli tools are very good for mail, IRC ...
When something is nasty, I can fix it with a specific tool (or script). I am free, I have a computer that fit my needs.
KISS (a concept that I honestly forgot) is a winner for me.