The wider flower part allows good light and air into the decks below. The bulb part holds yet more people with good living space. The venting and design can be ecological and environmentally active. Each flower has good spacing with road networking up to 4km away allowing for a one wayness of nature. Some areas are more built up than others and along with nature a good heratige should be preserved. That's how you deal with 420 people per square km like in England and leave space for nature. Along with a few super farms complementing good free range local farming and artificial trees for collecting both solar and wind or tidal energy.
You could still own a car in such a world but you would need a small ev, or someone or something to drive you to your car in the multistory car park. You could also pick up deliveries at the car park. Your automatic right to a spot would be based on where you live.
Nano materials with bonds that can be broken with a bit of electricity at a specific frequency range and can be rebonded into something else could replace plastic in some areas alongside fully compostable packaging and other natural and ecologically sound fiberous materials.
Also by using rebound able nano structures the repurposing could save on energy and be more efficient with some aspects of product fabrication.