I think the smudging is well done but more golden tones in the background would really add to the epic feeling of this scan. some of the lines around his face and ish though seem jagged which isnt a problem normally but i think it doesnt fit with your idea.
i do think you shouldn't have done the edge smudging by his arm--it makes your wall look less professional.
just some cleaning up and adding colors here and there and i think this would be a phenomenal wall!
(ps: gonna complain about the sig too, just doesnt mesh)