Looking again at a favorite photo of a pre-war Usonian, and finding the original rendering of Sweeton (in matching perspective and lighting) in Taschen III, I like the comparison: pre-war and post-war Wright, one in brick-and-wood, the other in block-and-asphalt . . .
Rosenbaum, early photo
Sweeton, initial rendering
For me, Rosenbaum is shown in its finest flower, not to be improved by later changes, while Sweeton in its first outing is pure and even, perhaps, incomplete, the composition enhanced, along with the square footage, by the addition of the workshop ell and with the final roof texture (see the last of Dan's photos above).
SDR