Here is an attempt to simulate fabric and leather, everything is procedural except the bump/ roughness map.
After doing the test, I realize something:
Procedural map is awesome and suitable for non-moving objects.
For characters it is probably not going to work if he moves around.
That's my presumption, correct me if I am wrong.
I guess it's going to work the best with sets, props, to save some valuable vram.
(ps. somehow I think the circular pattern on the hair part looks pretty cute, stylized in a way.
Yes? No?

Question: in terms of the black contour line, is it caused by low poly count?