I am pretty happy with my configs now, with home manager but no flakes so far. I am, however, annoyed by all the dotfiles that I didn't define, and I'm worried how many other files are laying around without getting imperatively defined.

I'm sort of picturing a kiosk mode, where every time I reboot everything is wiped and I only have what I defined. Any files I want to keep are on other partitions or network locations mapped in my config. If a new config file is created by changing a setting in an application, I want to be notified so I can add it to my Nix configs.

Is this possible? Is it a terrible idea?

The biggest challenge I see is in installing games, because it looks like they often leave bits all over the place.