I wanted to have fun with this game but it wouldn't let me. Digging needs some serious fixing.
I'd recommend reducing all dig times to <= 2 seconds, and making diggable things rarer to balance that out.
If you want to go with your own solution you might find find this interesting. It's about walking, but I think most of the points brought up can be applied to digging in this game.
I'd also recommend limiting the distance the flashlight can shine so it doesn't 'detach' from the flashlight, which breaks the immersion/atmosphere you had going.
It's nice to see this genre get explored, there aren't any good MT games that do so yet. I look forward to future updates.