From what I gather, there used to be, the "streetcar suburb" was exactly that. It no longer exists, at all. best you may get is some new urbanist toy town in the exurbs. They're great because they're better than a regular suburb, providing local walkability, but they're still isolated pods.
A start for that would be investors legislating for building codes to be suspended in a new development area completely, allowing for mixed development. Then make a investment into public transport towards the area taxfree.
