The image below, courtesy of The Oatmeal, is mildly NSFW (if clothed cartoon penis bothers you, then back away now) is a perfect summation of what's wrong with the variant Spider-Woman cover.
This is the Spider-version of the gender-swapped boob window, and it's spot on. It's not the anatomically-impossible pose that's the only problem. The female character's being sexualized in a way that a male character in the same pose isn't. Understand that this humorous Spider-Man pose and package is just as ridiculous as the Spider-Woman #1 cover.
Plus, I have always wondered where Spider-Man's junk was.