I've tried this option for around two weeks now and yes, this looks great!
My only feedback is to maybe still poll HA for updates when an action is executed on the watch? Like when a script or toggle is executing, then update entities. It would look more snappy, and you would know the user is currently using the app, and it's not on "idle".
Suggestion: After an action, wait a much shorter period and then update before reverting to low power mode.
Follow on from https://github.com/house-of-abbey/GarminHomeAssistant/issues/103
Suggestion: After an action, wait a much shorter period and then update before reverting to low power mode.