We should build a "car-free" city just to see how well it will go.
* Large percentage of city is green.
* Most of the city is mixed retail+residential.
* Lots of 3-5 story residential buildings to have appropriate density.
* Streets have a single one-way car lane + two bike lanes + two walking paths + green space.
* Bigger roads are 1+1 lane, and primarily used by buses, commercial vehicles, emergency vehicles and people with mobility disabilities.
* The city should not be much bigger than 10km x 10 km. That's enough for 0.5-1 million people, while small enough that a regular person can cycle end-to-end.
* High-speed train access to nearby cities.
Since, this is a new city people who looove cars don't have to move there. So nothing for them to complain about.