Took me 9 minutes to finish.  Definetaly add mouse controls, ability to change our skill loadout, make us notice every block we mined worths more, let us see what we mined at the end of the run, add more upgrades and most importantly damage upgrades. Make upgrades that are useful (Why would i need to make bigger jumps when i need to dig down?) Add different tools which costs ores not just money. Add helpers or workers that digs for us together. Game should be simple so our only objective should be finding the treasure which could be at 1M depth.