One (hopefully last) quirk: as defined above, snap restart foo will start foo if it’s not running, whereas snap restart --reload foo will not. Documenting that is tedious, and using that is confusing.
This is because --reload changes systemctl restart (which starts services that are stopped) to systemctl try-reload-or-restart (which doesn’t). There exist also try-restart and reload-or-restart, either of which would make this problem go away. Could we change it?