If all the legs are going to be black, then I'd keep all the heads black, too. So in the case of the dark purple print, I'd make the sheep body the lavender so you can give it a black head (lots of contrast between those two fabrics), maybe with the purple print for (accented) ears. Anyway you do it, though, it's going to be adorable. Great pattern you came up with, especially those jiggly legs.