Kate is prettier than Diana was at 29, and will age well.
Diana was a knockout in her 30s, but Kate will be even moreso.
I wish I could post some photos of Diana. There is a gigantic black and white photo of her in the National Portrait Gallery that comes at the bottom of one of the staircases. It is placed so perfectly that people gasp when they see it. She is youth personified in the photo although it was probably taken when she was in her early 30s.
Diana was also accused of anorexia (as well as bulimia).