Thanks a lot for playing!
What you mentioned was one of the hardest design challenges I had haha
1. My vision is that the player would be hopping around the asteroids, but it had to start somewhere. Then I realized that you can just stand shooting and escape only doing that, which led me to introduce two things: the slow initial rate of fire + the different asteroids with harder to break ores. Ideally they would crash onto your platform and force the player to move. I think that going forward the best way is to have the initial platform collapse itself after a couple of seconds, instead of hoping that the random generation of asteroids would crash into it.
2. The ship was an idea of a non-conventional timer, but that clearly led to confusion :( Since I want the game to be 3 waves long and the player needs to survive that long, I think going forward I'll remove the ship and add a counter as other comment here suggested.
Thanks again!