Well done FB!

He looks too "clean" for me.
Add much more wrinkles, spots,lines, express skin bump texture.
teeths looks too thick...give them more volume.
Make color texture more dirty bellow the nose, add some red spots,lighten up color texture.
I would aslo give the neck more old look, more skin folds...bla,bla,bla...I talk too much.

Anyway its very,very nice peace of modeling.You defently got a potencial!

Good luck mate!