Xoliuls shader looks a lot better than marmoset, i think maybe its the bloom in marmoset that washes it out for me. The model and texture look great Arac, i would not have guessed that this process is new to you.
Alright, I worked on reducing the scratches, dents and noise. Here's the final result. First 3 are with Xoliuls shader in max, the others with marmoset: