Is this your first big project in Pico-8? Because this is very a very good result!
Initially I found it a bit strange you could shoot in one direction, but after figuring out the direction depends on where your ship is facing, it got a lot easier. The resource-collection system is very cool too - adds a great interaction.
I love following maps in games and this worked really well.
Also I went to the spot on the map with the cat swimming and didn't find anything. Not even a little easter egg? Ahah, just kidding...
Great entry!