Great article Adi! I think, cities thrive because they offer most efficient hence rewarding, coordination mechanism for cooperative human endeavors apart from farming. In terms of access to capital, talent, market. Coordination needs either physical proximity if trade is of material goods or excellent communication if it is not. In this sense, one way to look at holistic development is to create more & more avenues of cooperation & enable equitable access to them by policies & infrastructure. (education, better roads, energy, communications, creation of many small cities, strengthning peri urban interface) When rural GDP grows to match Urban, the migration will cease. For that to happen, agriculture has to be more productive. For which, it needs to be consolidated, use more technology and employ less people. If we make sure that cities deliver on the promise of better life, and there is upward mobility in slums, things are good.