The pixel art is amazing. It really impressed me, what you made with these 8 colors. Not only the ship looks awesome, also the UI is great!
Your soundtrack is also great. It fits the game's atmosphere so well! I love it.
What could you make better in my opinion? The small enemies are a bit to small, also the small enemy-projectiles. They do not stand out from the background so well.
Also the difficulty level was not optimal for me. The normal is a bit to hard, the easy mode to easy. And there could be some more pickups.
But overall, an awesome arcade shooter. Great work!