Is there a way to have Roomie pick the Home automatically based on location?
Simple answer is no. The only way to switch homes is to use the Activate button in the Homes panel.
Not a bad feature idea though. I’m not sure everybody grants location permission, and we only use it for the initial guide data location. Possibly we could look for the Wi-Fi network name in the Homes panel. Then there is the issue of people who have multiple Homes representing the same Home (like one for making new designs, and one that is “stable”). Then the basic issue that Homes do not currently associate with a location. Anyway, a few edge cases to consider.
Is there a way to use Apple Shortcuts to activate the Home? Then the automation of when/how to chose the Home is up to the user.