Discovery Wireless protocol … sounds promising. I am wondering if this protocol is compatible to WiFi speakers of vendors like Sonos, Raumfeld, Bose, etc. . Or will it be designed as proprietary protocol?
Also I would be interested in more information about steering and grouping zones (including audio synchronization within grouped zones, as ayou mentioned in your post), as well as information about routing different input signals to different single or grouped zones.
Could roon then be the ‘control-center’ in such an environment, adding featured information depending on the zone and/or clustering input sources by e.g. Performer, Genre, mood, …?