Enjoyed the art style and aesthetics, feels very thoughtful and deliberate. Although I found some of the text a bit hard to read and I think it didn't sit well for my eyes after a while. It felt quite punishing for the oxygen to decrease so much early on, that and the fuel "tax" after exiting a ship. I started to rely on volume at the start and just kept doing very small runs.
Even then, I just wanted to get some better upgrades and it felt like it was taking too long. As for the chance for oxygen to decrease randomly, I think for discovering new tiles it makes sense, but having it random on the way back seems unfair. If I knew how much a discovered tile would decrease my oxygen, I could plan better and the runs will be longer overall.
Also, the fuel cost increasing so much as I get further along was not fun, especially since my earnings didn't seem to increase proportionally.
With all of that said, once I managed to push through the initial portion, I really got into a groove and enjoyed playing! The music and clicking sound effects were really effective in drawing me in and building the tension. Before I knew it, I had been playing for over 30mins, even managed to almost clear out the entire upgrade tree. Great job!