Something long, he would look amazing with long hair. Doesn't even have to be a custom made mesh either. I would not mind seeing him with the sideswept hair mod or the undercut pony tail.
Courtesy of "Volek" from his Readme for his mod "Longer Sprinting". I dont know if he was the one who actually found it but I have copied the text from his Readme so i credit him. You sir, just saved my day. Thank you.