As adamesque wrote, it's going to be more like the Watch or even CarPlay. And I think this is probably the right approach, market-wise: Apple ran with the idea that every device needs its own standalone app ecosystem, to the point where they even tried putting an app store
in iMessage, and it didn't really work out. Apps on the Apple TV that aren't effectively "channels" (i.e., streaming services) have mostly fizzled, and I bet most readers even on Hacker News forgot that the Watch even had a standalone app store for a while. The HomeView absolutely seems like the kind of device that's going to do better with "companion apps": install them on your phone and let them install a little mini-app or widget on the HomeView. I don't need to manage a whole new set of apps on my smart home gadget---I just need to be able to futz with lights and the thermostat, listen to music and podcasts with the music and podcast app of my choice, and get to my recipe app if I'm going to be one of those monsters who puts one in the kitchen.
As for the battery, this doesn't look like a kind of device that's intended to travel with you room to room---but I agree it would have been smart for them to give people the option.