Marie Curie is undeniably one of the greatest female role-figures in science of the last century. I don't know why she isn't more revered, although perhaps are here are a few reasons why: (Note: I bring them up mostly in hopes of pointing out how silly they are)
1. Her work eventually killed her. There was no way for the Curies to know what effect long-term radiation exposure would have, but it's still not a huge image booster for her to have died from material handling practices that would be considered idiotic today.
2. She wasn't a "lone wolf". i.e. She did much of her work with her husband Pierre, who shared the Nobel Prize for physics with her. Pierre was an instructor when they met and undoubtedly gave her a huge helping hand right when she needed it. Never mind that she came from a poor background and showed remarkable determination just getting into college in the first place, or that she would later be the sole recipient of a Nobel prize for chemistry!
3. People are still scared of words like "radioactive" and "radiation". Just look at how comfortable people are with coal power that kills thousands every year as a part of normal operation. Then note how those same people freak out when a nuclear plant threatens to give a handful of people cancer, but only after being horribly mismanaged and then hit by an improbable sequence of natural disasters! Arguably, Curie is scary by her association with something people are unreasonably paranoid about.
4. Let's face it, Ada Lovelace was a bit of a looker, or at least she was painted that way. She even had a sexy sounding name. We have real, unromantic photographs of Curie on the other hand the reveal her to be rather plain by comparison, plus her name is now linked with a scary unit of radioactive decay! It's a case of the Belle vs the school-marm.