My city has been limited to 30 km/h for a few years now. As someone who is mostly by bike and by foot, sometimes in public transports and occasionally in a car, that has been a good thing. The city is small and full of traffic lights, and there's a ring road, 50 to 30 km/h inside the city can't be increasing travel time too much for cars. I don't think it was possible to drive at 50 km/h in most of the city anyway. (…
I'm fan of the concept of superblocks. You can drive inside them, but not between them. Want to go from block A to D? Can't drive through B and C. Need to drive out to the ring road, then follow it and into block D. Makes it so that no through traffic at speed goes through the areas where people live and stay.
Maybe it works out if it's a matter of fact and you move there and can find some place to live with awesome public transport but while I think ours is generally good there are some real holes in the coverage, especially the more you go towards the edge of the city. it's just not comparison. Subway stations are not 800m apart but more like 3.5km