@peteorrall
I haven't tried #TDE/Trinity, but I honestly never used KDE 3 or 4, so there's no nostalgia for me there.
I have tried both modern (as of a couple years ago) #MATE and the last Gnome 2 version of Ubuntu, and other than the clunky old application menu, I immensely preferred the look of classic Gnome 2. It just felt a lot more crisp and contrasty, even at exactly the same screen resolution.
I have a lot of love for #XFCE, but less and less for GTK, which it's built on.
I have a hard time hiding my disdain for things like #ClientSideDecorations, which I think is one of the dumbest ideas to come out of (I'll say it politely) UI Design, ever.
I liken #CSD to having a car's steering cluttered with buttons for the stereo, A/C, and transmission shifter, so you have to stop and think about where you're grabbing it before turning the wheel. Just a terrible idea.
My other major UI gripe: Lack of contrast between active and inactive titlebars. They took something that was split-second-obvious and made it a silly aesthetic choice. EVERY SINGLE DESKTOP AND OS does this WRONG by default.
Sorry for ranting. π