I m using Natural mode both for TV n BD
Backlight - 25 (Day) 15 (Night)
Brightness - 0
Contrast - 40
Color - 25
Color Tone - Warm1
All other settings r auto or at 0

This my own liking n preference, online settings just for guide n understandings

Also l find that these 2018/2019 Samsung TVs r good at upscaling. I mostly watch BD. Even tho my Oppo 103 can upscale to 4k, the Samsung processor can do a better job so l turn off all upscaling at the Oppo n let the TV do the job. The end picture is much better at 1080 / 60p. No disturbances at all, smooth