I be goin' to give ye some examples o' how Gradients be quite useless with proper color application.
This be a more abstract image, but it be showin' that ye can make a picture up o' seven colors, if ye just be usin' one to fer bright colors, and one fer black to give the illusion o' depth.
Here be another example, but with many more colors. This picture be usin' proper shadin' and highlightin' fer the subject in the image. This should be what ye strive fer lad.
I be hopin' that this teaches ye that Gradients be quick to ruin a picture, rather than save.