I am no more using the blending modes. At this stage of the pipeline, it is preferable not to use color-related or lightness-related blending modes. Allow me to quote @anon41087856, as he explains it very well in this other thread:
So now, I am always using only one instance of denoise profile, usually in non local means mode, and I use the central pixel weight parameter to control the amount of reduction of “luma” noise vs “chroma” noise.
About the adjust autoset parameters slider, this slider maybe won’t give you big differences in wavelets mode where it changes very few parameters, but it gets more useful in NLM mode as it allows to set quickly almost all NLM parameters at once.
Basically, increase this slider’s value if the image is underexposed and you compensated the underexposure in post processing.
Increasing the slider’s value will:
- increase patch size
- increase scattering
- reduce shadows preservation
- reduce bias correction
Indeed, NLM was only good for low ISO images before, but now it is working well even for high ISO images, and now I almost always use NLM whatever image I have to denoise. 
The change that made it behave better for high ISO images is not the central pixel weight though, but the scattering parameter.