My raw development (with dcraw and ImageMagick) ends with a 16 bit/channel colour-balanced image with values from 0 to 65535, and sensible contrast. It usually also creates a version with adaptive histogram equalization in 2x2 tiles (as documented in Adaptive auto level and gamma). I’m considering adding an automatic Crop to detail, because it often suggests ideas I hadn’t thought of.
Automatic tonal adjustment is by power curves and/or sigmoidal (S-shaped) curves. I usually care about the overall lightness (the mean) and the contrast (the standard deviation). I haven’t yet found an algorithm for the computer to decide what the overall lightness should be – low key, high key, whatever.
For adjusting tonal levels (lightnes and contrast) manually, I use curves, typically adjusting the L channel of Lab. That’s the overall control, but it might need local control, which gets messier.
FWIW, I don’t a perfect tool or system exists. Digital visual arts, including photography, is still quite young. We are all learning. We do stuff and see what we get. We look at what other people are doing and think, yeah, I’ll try that.