It's a decent start, nicely done! I'm liking the hi-res look of things, the ship sprites and enemy sprites look really cool and I'm enjoying the projectiles and effects too! I play shmups a lot to relax and enjoy the genre, so I'd love to see this do well, so a few suggestions if you wanted to take things to the next level:
- Big swarms of enemies! It gives a cool sense of power to the player when you can blast through ranks of weak enemies, in between fighting the tougher ones, go for almost constant action with hardly any breaks. Putting them in cool shaped formations helps too.
- Higher player bullet speed, fire rate too maybe. Just increasing that a tiny bit makes things feel more immediate.
- Super tight hit boxes. Always good to double check the collisions on a game like this, it's often best for the player ship's hit box to be a little bit smaller than the size of the sprite, you get more "that was a close one" type moments!
Best of luck with your development!