Pretty fun! A pause button would do it some good though. Was kinds annoying that whenever i wanted to 'pause' during a mining run I had to run all the way back. Sure, the whole map can be run through in like ~1 min, but that's with max upgrades (which I got, all hail the Oxygen God. Amen).
Ive seen other comments, and it is defintely annoying to run back and forth. Considering the time to run back, it's definitely a mental thing, but still important to address that to make a more engaging game.
At some point I started making a one-block path across the map (got around 50% before deciding to finish the game), and only moved in a straight line when exploring. Definitely made the final part a bit less interesting, cause I made it : PRESS DOWN for exactly that ~1 minute.
Oh and I totally wouldn't mind that it if in a future update, any bullets missed would stay on the map to be picked up later. Felt kinda bad to just lose even the few bullets I lost (even if I had more than enough). Definitely not as important as the other points though.
Cool Game!