@MRM is it too late to resculpt the clothes? A lot of it feels too muddy. There are few noticeable strong planes and sharp transitions in between the flows of the wrinkles.
I really, really love this, it has that great balance of simplicity and accuracy. And of course the rendering is great too - a nice and sharp lighting setup. Congrats !
Create a separate mesh chunk for the lens, give it a new material, and then set spec sharpness either really high, or to zero(full on reflection) in marmoset.
Lovely! So crisp and sharp... and I hear people complaining that even as much as 1024x1024 is not enough to do a character, evidently it's all in the artistry and execution.