... all female characters have a tendency, over time, to graduate to the field of, “tough girl with an air of innocence and also you’d like to get her pants off.” It would be an interesting experiment to establish five female characters between the ages of twelve and sixty, with a broad range of body types and personalities, and see how long it takes mainstream comics to transform them all into the 22-25 year old age group, with short skirts and colorful panties.
Time, you see, moves differently in comics. It takes a fourteen year old girl two years to reach twenty years of age, while a twenty year old girl takes fifty years to reach twenty-one.
-- Paul Tobin, explaining the frustration that many readers feel about Mary Marvel and -- really -- most female superheroes. There's not a lot extra that needs to be said other than I'd love to see that experiment play out.