This is an attempt at creating a dirty old iron NMM effect, as opposed to something bright and polished. I used cast iron skillets as inspiration here.
I like your style. Good ambiance. You made a very good job on the leather texture and the NMM.
Just a little critic: I would push a little bit more on the middleshade of the skin especially on the back. It's seem a little bit flat in front of the rest of the mini.