Very nice concept and game. I also liked the graphics and atmosphere the game has a lot.
It took me multiple tries to beat the game because of oxygen issues but after learning the mechanics I managed it to do it! Having to drill the exact spot of the ores was the most important thing to learn, with the addition of not always having to press forward to conserve fuel. I know the ore part was mentioned in the instructions though, I realized that after restarting the game. Maybe making the air deplete a little slower could make it more enjoyabe for new players.