Before I really comment on anything else regarding the game I'd feel really bad if I didn't clarify two or three things. I didn't code anything in the game and I didn't even design the layout of the UI. The main four note little goofy leitmotif of the soundtrack was originally played by a friend of mine who releases music under the name Krejcis Cornucopia on a night we were jamming together over the rhythm riff of the first stage. All of the drums in the entire soundtrack except for the main menu are just chopped samples of Jim Dooley's royalty free drum jam tracks for tone reasons.
When I was rearing up to release the thing on Steam last year I had a job working in a kitchen at a nursing home but I had a panic attack that made me feel like I couldn't come in one day which made me quit. I would've had to have 100 dollars to spare in order to get it on whatever Steam Greenlight is called these days and I promised Remtaine I would've personally funded it when it was earlier in development. I still feel pretty bad about getting his hopes up and not explaining anything afterwards because I was embarassed.
After it dropped I posted to a subreddit the master folder for the game that I found on Remtaine's GitHub after asking him about making the game open source. I've seen a lot of good things come about from heavily modded games like Half Life or Fallout New Vegas where the mods sometimes ended up becoming standalones and I thought it would be cool to try officially endorsing that kind of behavior rather than looking the other way and whistling like most devs do. It was my first ever game so I don't exactly know if it was the most smart of career moves to pull right out the gate but I figured it would make the concept a little more ubiquitous by making people less timid to share it around Orwellian copyright enforcers like Youtube. Anyways, I neglected to check if the code on the master from his GitHub worked or not before I posted it up. Turns out it didn't.
As for little things I'd change or add if I ever got the opportunity to do a sequel? Those homing rocket enemies would be nice to lure into exploding on other enemies. I've also got an idea for a new mechanic that'll boost the skill ceiling up a bit: the graze meter. By grazing against bullets it fills up and you can either spend it in chunks by pressing a button while a bullet is grazing you to send it back to the enemy as extra damage, OR you can wait for the meter to fill up to boost all the way to the next wave/do a heavy hit on a boss. If people try to cheese the mechanic by chilling next to the first enemy then the next waves will just automatically pile on after a set amount of time to make life harder than otherwise. No promises though.
The whole game is honestly one big allegory for the process of believing in Absurdism. The first stage is fighting one's own nature to search for coherent meaning. The second is fighting the notion of being ostracized by one's own fellow man for being an 'edgelord' or 'outsider' and realizing they never thought about you at all in the first place. The third stage is accepting that catharsis is fleeting and the joy is in the doing. Call me a monster but I honestly wish I told Rem to make the final boss just burn you to death as soon as you get to it. It'd put a nice little bow on everything.