I think there is relatively faulty design of Group of zones and their management. Once I add my device into the Group the only way how to use it, is via that Group ie all the other devices in the Group get power on and do the playback.
What I propose is following:
Once device (endpoint) is added to the Group; it should also stay visible as a single Endpoint. Means I have to have option to select only single device or Group to which device was added. So based on my needs there should be option to stream to only single device or Group (ie multiple devices added to the Group).
If someone is using exclusively Group (and all devices inside) and dont need a single endpoint device which is part of that Group; there should be a option to hide that device from List of the Zones.