Answer:
I believe The artist did this so that the drawing/painting would look neater and more easier to understand instead of catastrophic and messy therefore leading the viewers eyes to look at the main concepts of the image rather that several miniature concepts thrown together into one whole. 
Explanation: I’m an artist myself :)
 
        
             
        
        
        
Answer:
What is the Rule of Thirds? The Rule of Thirds is a general guideline for how to create an interesting composition which states that any image—painting, photograph, graphic design—should be broken into a grid with two vertical and two horizontal lines, creating nine equally proportioned boxes.
Explanation:
 
        
                    
             
        
        
        
Answer:
I would give this a 9.999999! You are a very talented drawer! I could not draw like that to save my life! It's AMAZING! The only thing I would say is that the lips are a little big. Other than that, rock on! It looks GREAT!