After the river 0.4 release I migrated from river-classic to kwm, recreating about the same design I've used for years now.
The image is a combination of three separate screenshots of the same screen. It shows a 'fake-busy' terminal (foot) based workflow featuring neovim, yazi, aerc, senpai and newsraft.
See https://codeberg.org/proycon/dotfiles for dotfiles
I looked for something that was similar to river-classic, kwm seemed the most mature one, but they're all very young of course. it's heavily inspired on dwm (includes a similar bar too) and the the developer is quite responsive. I do 'miss' the riverctl-based way of configuration which I liked in river-classic, I believe only zrwm (https://sr.ht/~zuki/zrwm/) currently does that. I haven't tried them all yet as some lacked features I need/want.