Imagine this... A universe (or solar system, rather) based on an alternate history of the 1930s based on the work of Heinlein, Jules Vern, and others.
I've been toying with the Rocketship Heinlein available on orbithangar, but there is much more potential in terms of different kinds of spacecraft. And when I say different, I mean different!
No engines? No problem! Just hop aboard a Jules Vern Spacebullet for a quick launch into orbit via a massive cannon.
If you're not in the mood for turning passengers into puddles of red jelly, why not take a ride in the space blimp?
These are a few concepts that I've found. I also would be interested in a sort of steam-powered interplanetary ship that can "refuel" at stations on the polar ice caps of moons and planets.
As far as space stations go, I have been able to find absolutely zero concepts based on the ideas of the 30s. I think most people back then viewed future spaceships as totally self-reliant; islands unto themselves. But you can't just hop into space without a destination.
I think the Big Wheel available at orbithangar would make a good stopping point for vessels bound for Earth orbit. It would probably be best if it were placed in a parking orbit above a major spaceport.
As for spaceports, I've thrown two moon bases together: Climatology Outpost #5 and Copernicus Spaceport. I plan on adding a large spaceport on Earth in Butler, Missouri (Heinlein's birthplace). I could also add quite a few others throughout Sol.
As great as all this sounds, I have one problem: I've never made a ship addon, and I'm having difficulty with learning C++ code. Besides, the artistic part of my brain never really came to fruition. I can include several addons in a package with the authors' permission, but things such as the Space bullet and the space blimp have never been modeled.
I'm going to try and learn as best I can, but I may need some help if I want to go through with making this beauty.