don't forget 4) Better urban planning so people don't have to commute in such great numbers / such long distances
The rest of the streets connect to people's homes, they're full of speed bumps and such and while some do go through, it's a slow and twisty road with no certainty unless you know that street (or peer at the GPS) so you'd never take those roads unless you actually wanted to go into that community.
I find that it strikes a pretty good balance between helping people get where they're going and making sure that people don't have tons of cars zooming right past the front door.
In many places the terrain simply won't allow for a regular grid layout. From my home in Minnesota I can't really go straight north, because there are a number of lakes in the way. There are a couple of roads that manage to snake their way through, but it's all fully built up areas that keep their speed limits low and safe.
https://www.google.com/maps/place/Phoenix,+AZ/@33.5083959,-1...
It was pretty nice when I lived there, because getting places using the highway was fast, and then the grid pattern for the rest of it made it incredibly easy to navigate.
The urban planning that would be necessary to slow down but not stop the rising tide would be one that makes property access closer to egalitarian ideals, so that the San Francisco or Palo Alto worker making $60k can also live there without driving far. Homeowners would rather experience more traffic / a battle with Waze than see property prices drop that much. The egalitarianish access to property is an even worse proposition for them by magnitudes.