I understand better the relationship to the theme now :)
About the difficulty, you could adjust it by adding some health bar. Like you get hit 3 times before being destroyed (with some invincible frames). You could have a different sprite to see a half-broken ship before exploding too!
I’m a pretty “HC gamer” and I think the first level took me the most tries, mostly because I was learning the gameplay.
Anyway if you think about expanding that game it could work really nice as a mobile game too. Feel free to hit me up on Discord (VikFro#4956) if you want more feedback / help in the future :)