With one difference: I think someday we will solve the biological problems of zero-G, and spinning large colonies will no longer be essential. Once this happens, they become orders of magnitude easier to build from raw asteroidal material.

I did develop a vague idea for making spinning colonies that were practically size-unlimited. An inner pressurized torus, and an outer shell made of asteroidal material, hundreds to thousands of feet thick, with a semicircular "track" like a bobsled run on the inside surface into which the pressure hull closely fits. Between the two: some advanced form of magnetic repulsive bearings. The inside hull rotates, and the centrifugal force (don't start with me) is transmitted to the outer hull which does not rotate at all. The outer hull can be as thick as needed for radiation and structure, and its own weight will not be added to the spinning loads.