The urban sprawl isn't very efficient and we have many houses with 5 surfaces exposed to the open elements. One has to be careful of vehicle traffic. The urban sprawl takes up a lot of the earths surface area displacing and killing off native fauna and flora.
We have issues with over exposure to UV light and walking outside when temperatures/storms are inhospitable. With the right structure we could walk under a protective environment while still being able to view the native life below making us less dependent on vehicles while separating people from vehicles. We also would be less likely to litter and more.
I'm proposing a city that has great interconnected glass like walls we live in, with great arches. People walk on top, domed off.
All for now. Image available.