Not gonna lie, it was difficult to discern the instructions due to the colors of the text of the background. A panel behind the text would help.

The rocket not being animated in the slightest looks strange. Could help to animate the flame a tiny bit. Even mirroring that part for the second frame could help. I also had to force-close the game to escape the tutorial ...

The minimap was a nice touch, even if a tad unoptimized.  I think rotating the rocket according to the direction it's moving would have helped a lot in making this game look more cleanly programmed.

Red background for hardmode. Nice.

If you were to iterate off this, I'd say adding a radar that detects things a certain distance away from the player would go a long way.

I am thankful for the dedicated tutorial. The bright green text on the busy background image in the menus was somewhat difficult to read. I would have liked to see the ship turn in the direction of its movement. The background images in the levels are noticeably compressed and blurry. Perhaps a smaller image that is then tiled to fit the area would work better.

The text in the help screen was difficult to read against the background image. The background music was really nice and appropriate. It was kind of neat seeing the backdrop with the particle effects. The game has some really nice visuals!