solvtr
I use Lawnchair and Articons Dark (FLOSS launcher and icon pack, both available in F-Droid, etc) w/ black background. With this setup, most apps (even obscure, FLOSS apps) are included already. The rare occasion you might find an app with no icon available, you can choose another that resembles it or simply "makes sense" as an icon for you with said app. There are thousand(?) of icons already. I've never had an issue with this.