This game is done very well and I really like it. I think it has reached or surpassed some mainstream similar games at present. Here are my improvement suggestions:
In the early and middle stages of this game, it was really intense and exciting, making me often forget to eat and sleep. However, in the later stages, it felt dull and boring, with little playability. It was just throwing away a few asteroids and tapping into technology, and I lost the desire to continue playing. I hope to improve it a bit. If possible, I am willing to pay to play some more challenging expansion content (such as developing resources and building factories on asteroids, of course, there are more interesting things than that)
By the way, please don't focus on the train for a long time, as a large number of players don't like playing with trains. You can improve the train while modifying other content.