"I do think that Miller has difficulty writing female characters, because most of his female characters existences tend to have something to do with sex: they're prostitutes, they want to have sex with Batman, they want to go on a date with Bruce Wayne and talk about in their underwear, etc."
Eh...it's more balanced out in his original work, I find. His Martha Washington is a very competant character, as well as Casey McKenna in Ronin, as well as Miho and Nancy in Sin City.