This rings less like some missing key points, and more like an entire, comprehensive traffic strategy. I'm not really sure what the point is meant to elaborate on. Maybe something like "Self driving cars in themselves wouldn't solve traffic, but well designed, purpose-built AV's combined with surge pricing and (when necessary, depending on the location and journey) trains/subways could do it." Did I understand you correctly?

Yes. In some ways I'm responding not just to the text but the subtext: I've repeatedly heard a line of argument that seems to say that AVs won't help city-dwellers and therefore they are not worth investing in. I'm saying both that city-dwellers are not the only people and that AVs will soon come in new forms that will help city-dwellers as well.