Caving vs. methodical mining

A lot of people seem to love caving (exploring caves and mines for resources).

I've come to the conclusion, however, that I don't like it at all. It's grossly inefficient, since all resources that might have been in them have been replaced by air. Even when you find a resource vein exposed on a wall, on average you're only seeing half of what would have been available.

But, my biggest complaint about caving is the inability to figure out where you are and, more importantly, where you've already been. My mind doesn't work that way. I've devised a way to track where I've been (using torches), but when the cave system is large, it becomes impractical.

Can we please get some kind of mini-map or even regular maps that work underground?

Even if we had a chunk map that highlighted where we've been at this level (level being defined at the chunk level as well), that would be helpful. Maybe show the current sub-chunk in one prinary color, and the one above and below it in a different primary color. Use the combination colors for where I've been to both the current sub-chunk and the one above and/or below it.

For example, have yellow be the color of the sub-chunk level I'm on. Red is above and blue below. If I've been to the current level (obviously yes) but neither the one above or below, color the cell yellow. If I've been to the one above but not below, color it orange. Below but not above, green. All three and it becomes brown. Never-visited = black or grey.