Surprisingly good and fun experience! I dare to say it's one of the most "complete packages" I played so far in this jam. From an outsider perspective, seems like you had an idea, imposed limitations to benefit from the idea (or vice versa), and executed exactly the way it was supposed to be. Fun and addicting retro game. Didn't get to use Apple II, but it reminds me of some great Atari 2600 I've played. Good work overall on all fronts. My high score was about 15800.
Just had one question, I noticed the music getting faster and the levels increasing, but the difficulty affected things in-game like enemy health or bullet speed, or the game is reliant on player mistakes? Personally, it seemed all my deaths was due to my wrong decisions so I suppose this is good arcade game design lol