Lighting needs an obvious fallback
People should be able to control essential lighting without an app.
Climate systems need normal controls
Smart thermostats should not make basic temperature control mysterious.
Access control deserves extra care
Locks and entry systems need manufacturer-approved backup methods and household access planning.
Document fallback behaviour
Everyone in the household should know the normal non-automation path.
Keep in mind. Compatibility is not permanent. Confirm the current manufacturer, platform and certification information before purchasing, resetting or migrating a device.