The first two builds were a little disappointing due to the lack of music and general sound effects... but that made the boss fight that much cooler cuz that song was like EXACTLY what I was hoping for. It was pretty badass taking down a huge ship and I'd really love to play a future version of this game :D
Also I love the end credits "scene" it reminded me a lot of the end of each level in star fox 64.
Something important to bring up, the camera tilting with the plane was really disorienting and the game would lag causing it to flip very far and made me a little nauseous :(. I get why it'd be cool to have in the game, but you might want to have a setting to turn it off for people who might get motion sickness.
Edit:
One thing I noticed in the first level was the health text was practically invisible because of the water. Maybe you could have a single pixel of another color to differentiate the ui?
Also I noticed that the reticle doesn't line up with where the bullets go which made it very difficult to take out the objects in the second level and the boss