For colored pencil this is quite good. I love that the grays are dynamic and full. You still perfectly captured biggy at his finest. The only thing I could imagine doing is burning on photoshop to make the blacks really stand out. A midtone burn by his eye/check/chin on the right could stand to be darker under the cigar/blunt. I scored as follows:
Vision 5 : Your concept definitely became a beautiful thing.
Originality 3.5 : The movie just came out so I saw a couple people do it.