Thanks so much for reading this! It's funny you should mention system-agnostic settings as I think that's where this game is heading. I'm starting to envision it more as a campaign and setting guide, rather than a supplement to Cairn. I've added image credits, thanks for the tip. If you're at all interested in more of the thinking that has gone into this game so far, I wrote a little blog post about it.
I really appreciate your thoughtful comments. I'm hoping that as soon as I have the time I can read through all of the other Train Jam submissions and return the favor.