Adaptational Attractiveness: Ursula's character design in the stage musical is less "overweight drag queen", and in the original cast, she was played by Sherie Renee Scott.
With Ursula as a major villain in it's Season 4 arc, Live Action Disney owned show "Once Upon A Time" also went this route not only making live action Ursula attractive in her current Octopus-woman state, but also showing her to have once been a very beautiful mermaid? before she became evil.

http://tvtropes.org/pmwiki/...ney/TheLittleMermaid
Фишка в том, что существует дофига фанатов Урсулы, которые считают, что она идеальна в оригинальном виде.