Heyo, this is a quick one day project to test the substance designer & painter workflow with blender.
The bump is not convincing. Otherwise the clay material looks good.
Do you mean a special part or in general? I think I could tweak the materials a little bit more but I wanted to test a fast plug and play workflow. Just one principle shader with color, roughness and normal map input, nothing more.
This part totally breaks the illusion. Especially where it gets around the corner. Looks flat and lacks geometry. the disadvantage of a normal map.
The bumps edges seem to be a bit soft. It should be very sharp.
You could also try micro displacement.