An update for 0.18?
Actually I do have a few things:
I've noticed that the game doesn't recognize the different types of belts as the same thing, meaning it doesn't attempt to connect a regular with a > or with a >> of the same tier, allowing you to nest far more belts around. I'm not sure how this looks at the technical side but an option to allow for additional, identical in length but not able to connect tiers of belt for even more salad could be fun.
If possible fix the upgrade planner not seeing the extended belts. When I have a Yellow>> underground belt and drag the upgrade planner over it, it'll replace it with a red regular underground belt.
And why not include a silly, late game fun option that's just an underground belt with an absurd length and speed to match? Can even be separate from the blue line. "Acceleration tunnel" for instance.