One suggestion: make it possible to buy missiles at the starbase. It's really hard to find them via drops; I had to destroy every ship in the secret weapon area to get maximum.
Fun, but has a small control issue. Often I automatically press '3' hoping to get it to switch to number 3, but it instead switches to 5. I understand why it does that, but perhaps in a future version you can pick? 4/5
If there is a Qoosh 2, there will be a level editor. I will expect payment in full.