AH Hah Moment
Color interest me a lot and I think that is one of the reasons I like to paint abstracts. I recently read this article which states so well the ingredients of a successful painting. It was especially helpful to me in painting the last couple of abstracts because I could use it as a test to see if the paintings held up to the guidelines in this article.
I will summarize it here, but check it out if you have the April 2014 Watercolor Magazine. Since I don't remember the proper way to give footnotes anymore, I'll list everything I can to credit the author and put it at the end of the summary.
according to Richard Ellinger a composition will be unified, regardless of color when
1. Hue, or a combination of closely related hues dominates the composition
2. One value, or combination of closely related values dominates the composition
3. One intensity, or combination of closely related intensities dominates the entire composition
4. There is contrast in hue, value and intensity in the composition
5. Hues appear in several places and are repeated throughout the composition.
(Some of this is copied from article and some is paraphrased)
Watercolor Magazine, April 2014, article by Donna Zagotta who referenced the book Color Structure and Design by Richard Ellinger, 1981
Donna Zagotta, the author of the article called "The Color Project" is a master of color, shape and value.