That implies there are more than a smattering of feminists reading them in the first place.
I'm of the mindset that believes mainstream comics writers, artists, and editors aren't intentionally sexist and, while they may set out to generate controversy, do not want to provoke the kind of response those books have gotten (particularly after being humbled by Batgirl at Con and swearing they'd do better). To that end, I believe that incremental change is possible through efforts like Laura Hudson's to get them to pay attention to what the hell they're doing and try to do better.
Gail Simone's original Women in Refrigerators piece got the industry to sit up, pay attention, and try to do better (and hire people like Gail Simone to help them). It's frustrating that we still have to have this conversation 12 years later, but it's a process, not an overnight change. There's been plenty of progress, and there needs to be plenty more.
Aside from that, though, the qualifier "mainstream" is important (if somewhat muddled). There are a hell of a lot of comics that aren't about superheroes and aren't published by DC or Marvel. I just, about 20 minutes ago, finished posting a comment at CA suggesting that Laura do a regular feature spotlighting books that DO have positive portrayals of women.
And while I'm on the subject, here's the first recent one I thought of: Optic Nerve #12, by Adrian Tomine, released a coupla weeks back.
The first story, Hortisculpture, is told as a series of four-panel gag strips; it bears a certain tonal and structural resemblance to Wilson. It's about a guy with a wacky invention who tries to make a living selling his art, and fails because the invention is, frankly, ridiculous.
But the reason I would submit the book as a candidate for Positive Portrayal of a Woman is the second story, Amber Sweet, about a college-age girl who learns that she bears a strong resemblance to a porn star and has to contend with harassment as a result. It's down-to-earth, slice-of-life modern alienation stuff; I'd compare it to Ghost World (yes, two Clowes comparisons in the same review). Great book and well worth buying, even for the $6 cover price.