Yup I would like to say Kimberly Hart is probably the most overrated Henshin Hottie. For me I am in the boat of overrating her and here's my reasons...
Yup I'll admit she was a rare beauty... she had that sweet, childlike pretty face and a sexy body with nice skin quality. Well for one, I was thinking her beauty may have even beaten every over Henshin Hottie before her and maybe after her. In fact, I didn't find Jayme Betcher (who retired so shortly after her only role) in Superhuman Samurai Syber Squad (which the title is so erroneous) all that hot. I would probably say that I was considering her the hottest Toku girl ever for her time!
For the Amy Jo Johnson comparison to Reiko Chiba and Natsuki Takahashi, they're all gorgeous in their own respects but it seems Kimberly catches more attention. I think most of the fanmade comment of Reiko Chiba or Natsuki Takahashi being hotter is either personal preference or unfair prejudice towards Power Rangers. And of course for me, every other Power Rangers hottie that came after her or Super Sentai hottie that came after her, I thought they were pretty but not as pretty.
I would probably admit MMPR was already getting cornier and cornier as the seasons passed by, even Lord Zedd wasn't really helping things imo. So yeah, I ended up just watching MMPR to admire her beuaty and wanting a girlfriend who looks like her. However when she left, things just started to fall apart for me and I really didn't like Kat out of an unfair bias. I guess some of her fanboys actually hated Kat too especially when the writers wrote that Dear John Letter. Plus I'll admit I watched that stupid Turbo film to see her but alas, she was wasted.