Boa Hancock is undoubtedly one of the best female characters in the series. Most people complains about her attitude towards men and Luffy in general but I think it adds more to her personality rather than degrading her overall aspects of her traits.
There are many people who seems to dislike this type of character, like Boa Hancock (reasons you stated), Vivi (naivety), or Pudding (her attitude).
If anything, these girls have character depths, not just girls with generic personality, or become common Luffy's worshipper.
If anything, their wide range of expression and emotions are a plus.
People are just quick to judge that girls who's not instantly wet for them is bad. This is very, very wrong.