Pic could be smaller, but it's also overexposed. Too much light--you can't see the colors. Don't use a white or black background for pics. Try gray or blue. Could go up to a seven with a better pic. As for the painting itself, it looks good to me. No crits there!
The large size of the picture is bringing your score down a bit, as people can see the weaker areas very readily. But it is helpful for getting good feedback. I like how you've shaded the blue cloth with purple, helps give it a magical feel. The freehand is fairly neat, but maybe needs another coat or two to look solid and not streaky. I think there's too big a jump in your layers, as you can see the edge of the lighter layer against the darker layer. If you mix a few more stages inbetween or thin the paint and do more layers you'll likely get a smoother look. Also CMON voters expect to see finished bases, so you're likely getting marked down for that, also. You have a lot of potential, I hope you keep working on your painting and having fun!