The game picks up pretty well after a few upgrades, going up after going down is a pretty nice game loop and it has a satisfying ending.
At first I didn't know where my character was, what any of the upgrades did, how to get ore or what what it looked like, and assumed that you had to dig down forever like any other mining game, but the game does a pretty good job of teaching the player all of these things and learning them was pretty fun.
The only obvious point of improvement I can think of is trying to find a way to do more of the teaching with gameplay and less with the statues.