Since there's too many uncertain factors in my setup, I'm gonna go ahead and do a proper calibration myself using the JVC autocal software. I'm picking up a Spyder5 Express tomorrow. Then I'll upload the Manni01 custom curve.Dark level = 5 is what is needed for gamma D, but that raises your black floor and kills your on/off contrast. Fade to black has significantly raised black level with that setting, especially as the DI is disabled with Gamma D. Lowering it to 2 (possibly 3 if you're lucky) doesn't raise the black floor, but crushes black and you lose a significant amount of detail in the low end.
That's the main reason why Gamma D isn't usable and why we need custom curves (or why SDR BT2020 was used before we got custom curves).
I hope the calibration process is not too involved. Will you guys here help me in case I get stuck?