Fedora Kinoite because it doesnt suck and doesnt break. Actually switched to ublue kinoite main, very close to upstream with minimal changes that always stay the same (its always the same difference, not weirdly diverging more and more from upstream).
But I dont know if it is the best model, as Fedoras BTRFS snapshots + ostree without the image based thing would sound better ? But this is not existing.
Btw Nix, Flatpak, Distrobox/Toolbox, Distrobox/Toolbox with root, Podman, Docker, layering, removal, are all things that work on Fedora Atomic. Maybe even snap if someone is brave enough to try