I used graphical user interfaces (GUIs) since 1993 and still abhor turn they took '95.
Starting '97 I gradually switched to UNIX/*BSD (FreeBSD, NetBSD) then GNU/ Linux (still prefer UNIX (stabler design/kernels)) and by mid-0s used them 50% time (mostly NetBSD, Slackware) then in '10s exclusively (mostly FreeBSD, Slackware, trying OpenBSD servers, DragonFlyBSD, Tribblix & OmniOSCE IllumOS UNIX desktops). First I used X/TWM on FreeBSD, NetBSD & Slackware which is great: likely fastest WM... soon used KDE3... was okay until KDE Plasma (KDE4 in 2007, most people I know immediately quit permanently) so started using TDE (KDE3 fork, now KDE4-influenced) & XFCE sometimes/often, much more this year. I also tried Enlightenment (E) and over 30 WMs/DEs available for Slackware (and last Summer FreeBSD) and apparently E is good but needs more configuration... didn't like anything else but heard ICEWM, i3WM, FVWM*, LXQt may be okay/good--if can configure from scratch or premade (any available?). However I prefer MLVWM (inspired by classic Apple, as is KDE3 partly), (Ns)CDE (apparently inspired by Windows 3, win3, but NsCDE is based on FVWM* so maybe a WM not DE)... they're all back! Are any WMs (preferably) or DEs (possibly, if fast) like a mix of MLVWM, (Ns)CDE, maybe KDE3/TDE? What I mean is win3-style program groups, and taskbar with systemtray & classic Apple-style system menubar (preferably) underneath, application menubar underreath. Program groups are superior to win95-style start menu (I abhor as much more difficult/sensitive/accident-prone) but latter optional as long as doesn't replace program groups, and submenus longer than screen have fast/full/onscreen/column cascading and not just newer (inferior) slow/partial/offscreen/scrolling cascading. I hate all GUI animations (other than shown while main GUI isn't ready but starting, like classic KDE3) but a few effects are okay though most are overrated/useless trends/fads or (animation, etc.) time-wasting/slowdown. In the case I use widescreen (16:10 or 16:9 though my main KVM switch monitor is fullscreen (4:3)) one useful effect (from Apple or Windows?) is snapping programs to one-half or one-quarter screen (as I have 4K so typically only use it all when making graphics but use half screen for programs average users use) and when doing that KDE has a related effect 'snap helper' that shows screen centre (vertical & horizontal). Another useful effect was KDE's display window moving geometry (showed window length & width and maybe position but if not would be good). Another useful-sounding effect was KDE's track mouse which claims displays a mouse cursor-locating effect when activated, but never worked for me... viewing configuration says it's set to <META> key, which if you play classic roguelike fantasy/dungeon game NetHack, was a UNIX term translating to IBM PC-compatible 101-key keyboard <ALT> key... recent years maybe people ignorant of UNIX/GNU/Linux history redefined <META> to one the two new 'Windows keys' I don't have (and never will)... but would still like this effect. Mostly I'd like a WM/DE that can work with 101-key IBM-style PS/2 or AT or even (don't have one, but highest-quality) XT keyboards. I tried many other effects in past, but some goods ones (in addition to window moving geometry) may be gone but if not trends/fads were more trouble than they're worth: decades ago I tried translucency then ended up with some transparent programs so disabled most effects since (use to disable all at once, but KDE5 makes you do dozens one-by-one). (Ns)CDE lately seem to have also copied win95 by adding several start menus, when one was bad enough and program groups are superior... at least in (Ns)CDE they don't disappear every time so if I start 20 or 30+ programs (typical) it's like program groups all in one go (and being reminded what else I may want to use until minimizing groups) rather than typical win95 & KDE & XFCE start menu over & over and one can only view one group a time (then disappears each time or if a program takes 'current focus') rather than all (and need not disappear) and if the system slows you may give up waiting on a submenu to open. However, (Ns)CDE still seemed extremely difficult to configure with too few options. KDE3 was good because had advanced configuration wizard including asking if one wanted Apple or Windows or other aspects, and eventually let one setup multiple screens & backgrounds (including slideshows on gradients). (Ns)CDE have no familiar styles and make assumptions about screens & backgrounds (don't recall where to change). (Ns)CDE improved because lately I can run KDE Dolphin file manager in one or both (didn't use to work or at least not with proper file/directory/ image previews). Only thing kept me using KDE through KDE5 is powerful systemtray especially night colour control which is unequalled, and I like KDE's taskbar launchers that disappear to change into current task boxes. However since KDE4 I noticed if you run something more than 10 programs (or definitely 15+) KDE4 halts--still true with KDE5--so never really has been 100% production-ready for power users (in sense of general/polymath scientists, Renaissance people, others who do almost as much). If you open 30 programs very slowly you will likely have no problem. They thought it was task manager so I deleted it and started my 18 most-used programs at once in a script which halted KDE but worked so perfectly/fast in XFCE I kept script for launcher. XFCE can also run RedShift night colour control which with configuration/improvements/bugfixes XFCE is likely much superior KDE replacement as long restores what XFCE hid/ replaced forking CDE (win3 aspects)... or does anyone think (Ns)CDE or revived MLVWM (if tried?) or something else that's only a WM (not DE) would be faster? Recent year even many XFCE users I know prefer older XFCE (many same people who immediately quit KDE Plasma permanently)... though I have more powerful PC than some of them, occasionally if I do most I would do in XFCE there may be barely-noticeable slowdown such as in start submenus opening but seems possibly best balance between features & speed. Forget GNOME/MATE--never liked since early days it was all text-file-only configuration on RedHat, though I do like GNU Image Manipulation Program and Eye of MATE viewer.