Your game is awesome! I really like the idea of racing through space or on other planets to save the world, haha. I loved the car designs, and the sound was fantastic!
The main thing I think it needs is a clearer definition of the missions and the actual goals , like collecting a certain number of items, surviving for a certain amount of time without dying, etc. That would make the gameplay easier to understand.
But it’s a really good game, and I really enjoyed playing it!