I really like the basic gameplay loop; digging tunnels for maximum ores while still trying to have good paths out is a fun puzzle.
Had a hard time with the climbing/jumping controls, often getting climb when I was just trying to jump and vice versa. The stamina bar feels punishing especially while just trying to jump up a one high block staircase.
The countdown to payments could stand to be clearer - when does the day start, how much time do I have left? I've lost multiple times by not being capable of figuring out what the game was trying to tell me in terms of time left, which was frustrating. A spindown clock face similar to the stamina gauge could help a lot there, or some kind of audio/visual cue to show "hey you don't have a lot of time remaining".