Personality is a lot better!
When I am shooting photos, I believe that the personality of someone is better because it can really show the true feeling of someone in a photo. Just because someone may seem pretty, does not mean that they will make a good conceptual photo. A photo needs to have a good emotional side to it as long as a good model. If the model is just pretty, then it will turn into a regular old fashion shoot with no meaning behind it unlike a conceptual shot of a girl crying. This is why personality is a lot better than appearance in photos in my opinion.