I have to agree with the people who said if they could dress someone up like Jasmine or Ariel, they could do so with Jessica. I mean, Jessica's assests are impressive, but take a good look at the waistlines on some of the animated Disney Princesses. A couple of them are worse than Barbie in their proportions. If a lovely young (human) woman can pull off Briar Rose, then Jessica is possible too. There is a certain amount of suspension of disbelief with any of the characters. Plus padded costumes can do alot. I remember thinking a real person could never look like Lara Croft, then I saw Angelina Jolie, with a little help from a padded bra, and I thought, well, that's pretty close!
I think it probably has more to do with Jessica's more overt sexuality (yeah, Jasmine is sexy, but she is also young and innocent, while a major plotline of WFRR revolved around suspicions of Jessica having an affair), and also the joint interests in the character by Amblin, etc.