I actually enjoy your game. It's pretty basic, the sounds fit well too.
Although, the game gets quite easy if you just decide to stay on the bottom. The challenge is far less difficult, I'd recommend adding in red blocks or spikes to force the player to move. I like that you have to time things carefully, although I don't think it fits the game very well. In an endless runner like yours, I believe something more along the lines of double-tapping would go down, and tap once to go up and avoid obstacles. Make the pew pew machine go pew every now and then, and have power ups to increase the rate at which it shoots throughout the game.
Wonderful job!
Here's my game if you're up for it: https://lyapunov.itch.io/orbital-one-procedural
I just recently put up a post about it too, if you'd like to leave your feedback there aswell.