PEAR BLOSSOMS
Watercolor - 11x15
I personally believe that the values - lights and darks - in your paintings are the most important design element for a good composition. Even more important than shapes or color. A few ways that you can determine if you have strong values is to:
Squint - this will immediately make the range of values and distribution easier to see and show you if you need more balancing or contrast
Red Film - use a transparent red film to look through at your paining and it will convert the image to a basically black and white, making the values easier to see.
Black & White Filter - use an image editing program like PicMoneky where you can convert your color image to black and white to see your values