twm can be made to look a little better than that...
Dropping the icons and iconbar is a start in the right direction IMO.
Default boot desktop
That's a stalonetray (tray) at top of screen and two xclocks below that (one showing the analogue clock the other is set to digital and shows the date). Background image is a simple 1010111 type bitmap
I've set the desktop left mouse press to show current open (active or 'iconified) windows, the middle mouse press shows a volume level selection menu, right mouse press shows the twm (main menu). That right mouse for menu matches right mouse clicking the three tray icons that respectively show osmo's choices (calendar/notes...etc), my own menu set choices (green liquid in a bottle icon that clicking shows firefox, xterm ...etc) and the third is LibreOffice -quickstart menu choices (spreadsheet, word processor ...etc).
Window title buttons have the 'iconify' at far left (window disappears totally other than being viewable via left mouse on the desktop), the X next to that is close window; On the right there's the resize (furthest right and next to that a zoom full screen/restore toggle.
This next image is a composite collection of the various menus all merged into a single shot
The pkg_info -mz shows all of the total installed packages ... 9 shown, but one (quirks) is a system security package i.e. not installed by me. i.e. the total number of things installed on top of the base OpenBSD 6.2 system (that includes X and twm ....etc).
To get my own menu into the green liquid tray icon I installed yad and I'm using a notification loop that presents menu/command pairs
Likely not anywhere near the best choice of code/script, but my coding ability is limited to more or less hunting around for examples that might fit and adapting that accordingly (for example I had to look up how to do a while loop).
Nice simple layout for the casual browsing type user (mostly mouse). If I were a more keyboard/desk or laptop user I'd probably go with cwm. For just 8 packages, two of which are small anyway (yad and stalonetray) that's quite a functional desktop setup IMO (browsing/pdf/office/calendar/diary/tasks/file management/video/audio/image editing ...etc.) and runs incredibly well on my 10+ year old hardware (2GB quad).