Sonos features I desperately need in my life and I'm sure other do too
1) The ability to create pre-defined / locked speaker groups for rooms (not just temporary ones by selecting each speaker manually all the time)
2) Locked speaker volume ratios within rooms (i.e. Front speakers should always be 10% louder than back speakers due to their placement)
3) The ability to set the DEFAULT sonos speaker that needs to react per each echo device.
I.e. If I'm talking to my echo in the kitchen I *probably* want my kitchen sonos speakers to do things. Right now if you say for example "Alexa, play Thumbprint Radio" it'll play it on the echo by default (You'll probably have to twist Amazon's arm for this one). Whereas, in an ideal world Alexa could rather start a dialogue with you, such as "Did you want to play Thumbprint Radio on the Kitchen Sonos?" Or if you say "Alexa, skip" and there are multiple streams active in the house it should either default to completing the action on the Kitchen Sonos or ask you "Do you want to skip on the Kitchen Sonos?" (This is of inserting behaviour intelligence/user shorthand for a longer prompt which would normally be "Alexa, skip song on the Kitchen Sonos")
4) Similarly to #3, when I'm talking to my bedroom echo I don't need all 14x of my sonos across the house temporarily reducing their volume. Just the ones in the room where the command originated from.
Obviously this would need to be something one sets up manually. Creating some kind of grouping of an Alexa/Echo device with predefined Sonos speakers.
I understand a lot of people want a lot of things - and you need to prioritize your development time according to features that fit the mass market, and that's probably people with smaller less extensive setups... But this is the direction where things will eventually lead in the "Smart Home" space.
Thanks for your time and consideration