What you're not about to see are the 20 pieces of scratch paper with unused design ideas, vague shapes, and design-dead-ends. What follows is what I finally came up with. New aero-ship designs. When I finish the new version of the game, they will be called Zephyr-ships, powered by anemoi (instead of zephyrium).
Visible on the outside of the hull are the lift-unit pods, strategically placed along the hull to provide lift while maintaining structural integrity. I tried to go for a 1920's era aircraft design, with a little bit of Chris Foss inspired hull shapes.
Up first, a light transport. Small, with six lift-units.
Second, a medium transport, roughly the same size and shape as the Serenity. It's got eight lift-units and a wider hull. Visible in the second view are some improvements, a little flat ledge that runs around the hull. You can also probably tell that the first design was originally much more rounded and curved on the bottom, which I didn't like, so I tried to straighten it out and flatten it more.
Finally, the heavy transport, the air-liner/heavy lift cargo plane of the Cydorian era. It's got ten lift-units and ten in-line propellers on two nacelles. It is the most intentionally Chris Foss-ian.
If I ever get time, I'll model these in DOGA.