I like options and variety in a breed... I'm more a markings type girl rather than color.
I'm more of a markings person as well. I like Millie's black and white, but I like it especially because of her spotted paw, not just because of her colors.
I know this sounds stupid, but I'm not exactly sure what color Lucy is. She looks fawn (or red fawn?) and white from a distance, but she also has bluish-black/gray ticking in her coat and a darker widow's peak of sorts on her head.
It also depends on the breed. In chis I love:
Tri
I love this deep red and white with a blaze
Sable, though it varies
I love red tri in aussies.
And bi black in shelties
I love any color in BCs, especially red and white and black and white. As for markings I love split faces, blue eyes, (especially just one blue eye). And I prefer rough coats, though I know that's not a color question.
I could go on and on, really, so I'll stop.