This was something that was brought up in beta multiple times. I made a similar explanation in another thread, but Ill paraphrase here:
Jay hasnt done full-length skirts yet because all of his attempts dont live up to his expectations. BaB didnt like the look of oddball colors on ice (and stone) so he limited the palette(s). The game is a direct reflection of their work, so I understand their hesitation.
Still, I would like to see a wider choice of color options for those sets.