Mining Game System - How should I combine a sandbox tycoon and mining game?

I wanted to ask this community for feedback on my ideas.

the game so far
Currently the game is a mining game that uses terrain. You can mine into the terrain and find ores underground.

possible directions
I already made a building system, however now I am questioning if it is worth adding. Basically, you can place down droppers, conveyors, and furnaces to refine and upgrade ores. The ores are the ones you mined yourself, and there’s a “base inventory” that the droppers draw from. However, I have other ideas

  • What if the droppers are on the side of the map so there’s more challenge connecting them up to your systems? Maybe this doesn’t make sense
  • Should I have to use coal to power the upgraders? It would add to the challenge of keeping the ores in check.
  • Should I even have a building system? Most mining games just make you sell ore. I don’t even know if the sandbox tycoon is a needed mechanic of this game, considering I also want exploration and stuff. There’s a ton of games with mining that do really well without extra complexity.

Any ideas about how this should work would be appreciated. Again, all that I have so far is a system for mining ores and a system for placing things down on your base. I’m pretty much open to any suggestion, even completely scrapping the building system! (although I want the mining to stay)