Nice attempt. I always wanted to make something like this. It doesn't feel finished though. It's more like an experiment.
Overall, I liked it, and spent some time gathering all the resources, mining out the whole mountain I had, and reach the top of the tech tree. What I didn't like is the separate key for interaction. It would be easier to mine/craft with movement keys. Mining out long tunnels whould have been a much better experience.
You should definitely continue the development and make this a nice little game. But don't overscope, 4 tiers of tools is already more than enough. Focus on the gameplay diversity instead.