Home automation: individuals components and grouping

When home automation eventually becomes mainstream, I would  like to have control down into smallest components, but also be able to apply my own groupings to have control at an aggregated level.

For example, a room will typically have several speakers. I would like to be able to control these speakers individually (allowing me to balance the sound based on where I'm sitting), but also in aggregate (changing the volume for the room up and down).

Likewise, rooms will likely have several sensors, for example several thermometers placed around the room. It might be useful to have one action dependent on the temperature of a particular thermometer, whilst otherse are dependent on the aggregate value (maximim, minimum, average, standard deviation, etc).