Now I can't really say much because you just explained everything.
I like the liquifying in the background, I personally think you over-sharpened.
I think you shouldn't blur so much, at least, don't be afraid to have your tags less blurred. The render doesn't really stand out. maybe dodge his face at the right size, to make it look like the lighting shines down onto him better.
(i'm at college and the cpus here have low quality so I may judge awfully wrong)
Kinda dark at the bottom while the light is shining there, which makes this look better in the left corner and a little bit in the right.