So basically, what everyone is saying is that "no" you cannot appreciatively increase dynamic range "in camera", except...
This is in fact the nature of digital-it's defect and why some Hollywood directors absolutely refuse to shoot digital: trade offs.
The problem is physics.
- Kodachrome film, for example has a 12 stop dynamic range, so fine-shoot in RAW.
But with everything, there are unintended consequences. This "famous" photo was shot on Kodachrome: https://www.pcs.org/assets/KodachromeFilm_AfganGirl_Banner.jpg
Yes, in RAW format you can get the detail in the shadows without loosing the highlihghts, but, what you get with a CMOS 24MP sensor is too much detail. In this photo you can count the hairs in her pores. Not flattering.
So why film is better (and you guys can argue about that) is the nature of silver halite crystals.
- They are of different sizes unlike the CMOS sensor.
CMOS
- They are not in a grid or linear pattern (i.e. random), and,
- they overlap each other.
[Silver Halide]
What I believe that you are looking for, as am I, is the quality of film: color reproduction, grain, dynamic range and depth-all of the things that make film look like it's alive.
Head over to Ken Rockwell-he can help.
I shoot jpg small, 6mp, use the widest aperture that I can for portraits (f/1.8), intentionally miss focus a touch, manually white balance for each shot (film never gets fooled-if you're outside shooting daylight film, the film gets the color balance right), reduce clarity, avoid non-natural light when possible and increase saturation in your presets. I sacrifice dynamic range for a better photo "in camera".
Your other choice is to go buy a $6000 Leica or a Nikon DF that will give you much more control in camera. And stay away from "G" lenses in the Nikon system (my opinion). Or you could just go buy a used Nikon FM film camera and some legacy lenses.
Good luck my friend!