The Movie "Bring It On".
What it promises:

What it delivers:

Vampire, The RPG.
What it promises:

What it delivers:

Products that have not been successfully marketed to a large market of women:
AD&D.
What it promises:

What it delivers:

New D&D.
Promises:

Delivers:

Dragon Magazine.
What it occasionally promised:

What it delivered:

Eldritch Wizardry.
What it promises:

What it delivers:

The game of chess. (Only 10% of chess players are female.)
What it promises:

What it delivers:

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My point?
Make the fucking thing you want to make. Make a game you wanna play. Market it honestly. Don't blame the artwork if women don't like it. Blame the retarded players at cons, maybe, blame society, blame the genre-as-it-has-traditionally-been-perceived, blame the game, but don't blame the goddamn pictures.
If you end up making a thing women don't like, slapping proud, powerful women on the cover won't help (and yanking the tits off the cover won't help either). And if women don't like your game but you want to meet women anyway, I hate to break it to you, but you're just going to have to get out more.
And as for the game: changing what you want to do because you think it'll appeal to someone else won't make them like it, but it will make it suck.