Love love love the randomly generated map, and the aesthetic works well.
I had some problems with the playability of the game -- sometimes my controls would get mysteriously hijacked and my ship would move off in a direction I wasn't even intending to move to like I had controller drift. No idea what causes it.
If there are two areas that I'd recommend you focus on, it would be variety and flow. Since all enemies just appear from the right and shoot aimed bullets directly at the player, there isn't a lot of variety, and it would be neat if different randomly generated levels tested different skills. Maybe one level has fast moving enemies that attempt to ram into the player, or one has enemies that shoot at a distance and run away, etc.
In addition, there's no real sense of flow -- enemies just appear at constant intervals at random positions. My suggestion is that instead of randomly generating every enemy in a level, I'd think that if you had various pre-assembled "blocks" or formations of enemies and then randomly generated those in a sequence, you'd be cooking with oil. Think Galaga.
Finally, like the laser attack, however, your main spread attack feels too slow and the fact that it uses the same bullet type as enemies do hampers game readability.
Looking forward to the final build!