2013 Fairytale Designer Collection
The 2011 Designer Princess dolls all definitely have their own head sculpts. Designer Cinderella and Designer Aurora may look most similar at a glance (perhaps also because they are both blondes with updos), but Aurora has sharper features, particularly with her nose and chin, and Cinderella generally has rounder features. The differences are more visibly noticeable in profile.
The Designer Villains dolls have unique head sculpts, though at a glance, Maleficent, Queen Grimhilde, and Cruella de Vil may seem similar. Designer Cruella de Vil has a more pronounced jawline and cheekbones, plus her nose is slightly turned up at the end. Designer Queen Grimhilde has a more prominent brow. Designer Maleficent was given a slightly longer chin and her mouth is sculpted into a smile, whereas the other two are not smiling at all. Designer Queen Grimhilde and Designer Maleficent have the most similar head sculpts, but there are subtle differences. The Designer Queen of Hearts, Designer Ursula, and Designer Mother Gothel have very distinct and unique head sculpts.
Designer Cruella de Vil - 09 by Shivatopia, on Flickr
Designer Queen Grimhilde - 04 by Shivatopia, on Flickr
Designer Maleficent - 05 by Shivatopia, on Flickr
Look at those nice, clear, beautiful widow's peaks on Maleficent and Grimhilde that they won't give Belle. Maleficent's in particular would be perfect for Belle.