I agree, this SHOULD work.
There are some so obvious people would want them things, that don't (yet) work it is puzzling.
Part of me thinks the lack of any competition for pretty much 2 years, has a little to do with it. It's hard to push yourself to be 1st in a running race, if you are the only runner.
Google Home should benefit us Echo users, as they know if they don't deliver, it won't take many years at all for people to say, "Why would anyone buy an Echo"
The other thing I wish was different is that, whilst they can't play the same music as you say as they don't know about each other.
If you add a smartsocket, and name it "Light" in one room, then get another echo for your home, that new echo will, thanks to amazon also know about the switch called "Light"
This is a shame, as you can't have a light in each room, called light, walk into the room and say to the echo in that room "turn light on"
Other thing I would like is voice recognition so that when you ask about reminders it tells you yours, but when your wife asks it tells her hers.
Google home had not even hinted at that either.
Let's hope, over the next few years, with a lot more customer feedback, and competition, we can look forward to a lot more improvements than have happened over the past 2 years.