The air quality is what I mostly look forward to. I bike 10km 1 way on my commute and it would be so much more enjoyable if the air quality was better.
Recently I’ve been thinking about how municipal air quality would be improved if stoves, furnaces, ICE and other adiabatic processes used stored sources of oxygen instead of the nitrogen rich atmosphere. Essentially turn everything into a rocket.
Of course there are some other tradeoffs about stored vs atmospheric oxygen.
I wonder if we couldn't use an oxygen concentrator as a first stage instead of relying on stored oxygen. This would obviously increase the cost of the appliance (probably by a significant amount) but it would be safer and less disruptive (no need for a new distribution mechanism and you can just upgrade existing appliances).