Seems that I had been out of the DE world for such a long time that I forgot how pleasing mild eye-candy can be. This evening I tried #picom again, after not using it for a long, long time since my LXDE days[1].
I'm quite pleased with how it bonds with #Fluxbox now, maybe it's time to rice again? :)
[1]: FYI: https://kzimmermann.0x.no/updates/20230131_1415.html