A comment by Anonymous
I'm using alpine with https://github.com/kedorlaomer/zinit. I have a base image with most of the stuff I need, and once I while, I update it (by booting into a normal system). When I think I need something extraordinary, I don't have issues installing it very destructively. A reboot fixes everything. Pros: immutable system, easy reset to known good state, experimentation encouraged, apps start instantly. Cons: Long boot time, permanent updates (add WiFi password, e. g) are cumbersome but possible, on old systems: little RAM left.