Hope you like it 
Some tweaks here and there, I think he looks better now?
Good job – he’s recognizable to me. I don’t see the Dexter character as devious as you’ve pictured him here, although I suppose his dark passenger could be pictured thus.
IMO, the hair is really killing this. Its hard to get decent looking hair in ZB, but you’ve featured it very prominently in this picture, and it looks very unfinished.
Also, on your tweaked version, you’ve lost some of your nice skin surface detail, and the lumpyness of the surface is more obvious. The overall shape is better though.