Lower the contrast one the first one mate and clean up his face and I think it will look better.
Second one... really don't think that smudge fits the render tbh. I think that c4ds suit it the best. Cuz it has the look to it with the equipment etc. Just suits it imo Also the smudge is too blurry. If you blurred it intentionally it isn't such a good idea. If you blurred for depth, I'll give you a tip. Layering helps a lot in creating depth for smudge signatures.
3rd is probs my fave. Not liking the colours but the idea is there.
KIU