It would be so cool if you could build a simple rail/minecart system to transport rocks and ores out of a mine.
Currently, the best early-game way to move stuff out of a mine seems to be moving stuff between stockpiles, which does not feel good doing. Carts are not really feasible because they require a 4:1 slope. Later, you research the elevator, but it also requires quite a large hole to be dug to fit in an elevator.
The minecarts I imagine would be relatively simple and should be available before Machinist is unlocked, e.g. with carpentry + basic engineering. You basically put down wooden rails and maybe pull the cart manually with a rope and crank at the top.