Yeaah, i noticed the timer thing too but i was too busy finishing the boss and fixing bugs. Though im not sure if i would put it below the score/health, maybe i could make it smaller and only show the text.
About the problem with the exploding ships, i could try to make it have a better difficulty curve by making it so the waves get harder the closer to the boss you are and make the bullet hitbox smaller.
Anyways, thanks a bunch for the feedback!