I had to create a portrait in Illustrator, using a photograph as a reference and need to get constructive criticism from at least 3 people to attach to my assignment.
Your feedback will be much appreciated 
I’m not quite sure of the purpose of the exercise. You’ve exact-traced the photo in some fashion in Illustrator. If I take your initial image and do a 6 color Live Trace on it, I get a better result though. The thing with Graphic Design is… Time = Money. If the purpose is to do a trace in the style of a Live Trace, just do a Live Trace, clean it up a bit (like where the dark area of the background on the right has become part of the hair that shouldn’t be there) and be done with it. That may sound harsh, but that’s the reality of the business.
If this is hand traced, be careful of your contrasts. The deep colors in the eye sockets and the very dark patches on the face give the initial impression of a zombie-type look. If that isn’t your intent, I’d take all the colors one or two steps lighter to start.
the blotches of black makes the person look like he is decomposing.
His most distinguishing feature is his mouth, the curved upper lip and deep dimples which should stay exact or more exaggerated.
the clef chin need to be the same on the bottom,
these tips are what i learned while drawing characters years ago,
Try this: