Yeah, you could.
We are planning to add a way to use a Chromecast in a display-only capacity. Most of the work is done, but we still have to build the configuration management that lets you link a cast device to an arbitrary zone in a display-only capacity.
The cast device doesn’t care if we play audio or not…we can just as easily launch it + have it do pure display of metadata while the audio plays elsewhere.
For a lot of zones with a TV that happens to be in the room, that will be a much nicer product than the rubber band hack 