Art
I really enjoyed the art style, especially the paralax scrolling with the background. Still, the water must've been pretty poisonous if the fish started swimming backwards.
Mechanics
It took me a while to understand that you need to change your hotbar slot to pick something up or play the hacking minigames (the latter I don't really understand why). I don't know whether it was necessary. From what I understand, the game would still function the same if you wouldn't have TAB and the hotkeys to nagivate your inventory and just made it so everything happens automatically. After understanding the system, I really enjoyed the experience. I wasn't also sure, how important hull integrity is. I mean, when does the hull break completely? How much time do I have? I wish I knew the answers to those
Controls
In terms of the controls, they were pretty unresponsive. I get the feel, you wanted to add to the game (i. e. slow movements in water), but I would say that it needs a bit of tweaking. I would personally increase the gravity, because currently it takes a while to fall down. Or maybe you could make it so the jetpack also allows you to lunge downwards to fall faster. Also implementing jump buffering would go a long way in increasing the responsiveness. It takes like a second for you to be able to jump after landing, so making it that you can press SPACE even before jumping would be nice.
Sound design
SFX and music were really enjoyable. They did the water atmosphere justice. It would however be nice if there was some music in the title screen so you could know, how much you need to change the music/sfx slider.
Title screen
Since I'm talking about the title screen - this is a nitpick btw - I find it weird that when changing between the menu and settings screen the window fades to black to reveal the same background. If the screen fades I would expect the background to change as well. Instead you could just make it so the text itself fades in and out.
Really cool experience! Congratulations!