The clouds especially looks to fake, and using a HDRI is in my opinion necessary.
But when making a animation it would be just beautiful with a more realistic sky so you can show the changing shadows on the buildings when the sun moves across the sky.
Different presets could be a nice feature to speed up the process
I do agree that low clouds are very fake looking. I usually turn them off and keep the Cirrus clouds which look better.
I always loved how Vue Ozone Cloud Factory rendered clouds in their software, which I am pretty sure is discontinued?