Thank you for playing and commenting! :D
You are correct, there's no time to learn the third and fourth ships. There should have been more content, and the third wave should have been more balanced. As you can imagine, we ran short of time at the end of the jam. :/
Holding the controller in different orientations and switching between them is the core idea of this game. We believe it strikes a good balance between making the player feel the ships are out of control, and helping them remember the four control mappings with muscle memory by tying them to the four holding position.
Thanks again for the review! :D