I try to break things down into flat shapes and patterns tying one shape into another forming an abstraction, for me this approach is the easiest way to find a strong design. It does not matter what the subject is everything when broken down will form an abstraction. instead of thinking what more can I put in I think what can I eliminate , what patterns and shapes can I tie together. I look for passive areas to play against active areas. rich color against gray areas. Compliments played against each other will create how dynamic the painting will be. This is the technical part of painting, what you are trying to express is what is most important.