Really nice game! I am a sucker for mining games so I really hoped this would be fun to play and it was. I played until I got the exoskeleton which took me a while...
The art is very clean and looks great. It is satisfying in a way that there is not clutter all over.
The mining mini game works fine, but don't use the release time of the buttons to register a press. Maybe entering the mining game could be handeled the same way as normal block mined i.e just move into it.
The queue up of inputs is a bit of. Having the ability to hold a directional button would make a great improvement. I must have pressed W a couple thousands of times on my playthrough.
Upgrades - The upgrades were ok, but it takes a bit to long to get them and they don't contribute that much. I would like an option to upgrade movement speed. Maybe have a marker or something you can buy that you can place in the level to mark your path. Fun thing would also be if the light goes out if you run out of fuel and it get super dark (and cold).
I think not having a compass or sense of direction is a positive thing for this game, it kinda makes it an important and additional objective to keep track on. And I think that for this game its the way to go.