On the face of it, in the absence of a planetary attribution, this seems an easy one, although not all the scales are present at first. On the ground in the background we have the yellow of the King Scale, as we do in the sun in the groin area, his boots, and his face. He is dressed in emerald green, while his bag is the Sky Blue of the Queen Scale.
Although the "brilliance" of Keter on the King scale isn't a color, I think this is what Harris was alluding to in the glowing diamond atop his head, while the dove seems to be the White Brilliance of Keter on the Queen scale. The background could be the Princess's "White flecked Gold" although it seems more gold flecked white, and I couldn't find that in the scales. It could be simply yellow, with brilliance.