In Ludum Dare 38 I made the game "Space Travel 15" (You can find it here https://ldjam.com/events/ludum-dare/38/space-travel-15). It was a game mostly inspired by Mini Metro, but with UFO's. The game was in no way perfect, but I liked the idea that much, that I decided to play around with the idea some more. So I have since then worked a bit on a game inspired by "Space Travel 15", "Mini Metro" and something like "Railroad Tycoon". I call the game "UFO Airlines".

https://www.youtube.com/watch?v=7ge60Nx7Vug

The idea for the game is to make something like "Mini Metro", but you have in this game much more control with how passengers are moved from airport to airport. The game is long from being finished, but if you like games like "Mini Metro" and "Railroad Tycoon", there is a lot of things you can play around with.

If your are interested in trying the game, you can find and try it here https://gamejolt.com/games/UFO_Airlines/474993