Thinking that my idea could benefit from having another point of reference, I added a "canal" pointed at the city. Changed out the moons, the colors of the aircraft, and added the lump on the elevator, which is its car. And added subtle colors on the buildings.
Really nice! But to me the aircraft's colors look a bit plasticky. I'd make them more metallic.
Nice work on these last planets images. Lots of ideas to try from your progress. Thank you for sharing! ;D