As a comic book movie fan who doesn't read comic books (my estimate is that there are millions of us), I have been exposed to Ms. Marvel by osmosis much, much more than Guardians of the Galaxy. I don't know where you're getting your statistics, but I would guess that there are millions more people who know about Ms. Marvel than GOTG. It's fine with me that they're going with GOTG, but I don't think you can pull the "other heroes are more popular than Ms. Marvel" card on whether she deserves a shot at a movie.
As for pitching the ideas to an executive, I think you'd have to be a real jerk to pitch Ms. Marvel that way. If you pitch her as a strong-willed, powerful superheroine who's able to go toe-to-toe with the big boys (as well as add diversity/new dynamics to your #1 team) and whose background would contribute to connecting both the cosmic and earth-bound sides of your still infant-stage cinematic universe, then yeah, I think you can get an executive just as intrigued as a talking raccoon and a walking tree, if not moreso.
I wasn't pulling the other characters are more famous than Ms. Marvel card, I was pulling the "All the characters who are left over are unknown to the general audience, and thus should be chosen based on their ability to deliver a unique and compelling cinematic experience, instead of which of these virtually unknown characters are more famous."
The general audience is what sells these movies, not the fans. The fact is, if you tried to sell any of these movie characters based on who already knows them, they'd all bomb. Whether they do a Doctor Strange movie or a Devil Dinosaur movie next, the majority of the General Audience will be introduced to the character for the first time. Even the most famous character marvel has left are barely famous at all, and thus fame should not be a factor in deciding which characters get movies next.
Maybe I was being highly cynical with my Ms. Marvel pitch, but I just feel very cynical about the idea of fabricating back story, and history for a character just to crank out a movie for her. Ms. Marvel's comic book career is defined by two steps forward and two steps back, with no interesting story arcs that weren't defined by her interactions with more developed, more popular characters .
I think many of the ideas being put forth here draw more on other Marvel characters (Having Carol replace Abigail Brandt in SWORD, tying Carol into the Kree Skrull War) then things that are actually inherently part of the character, who was created to be the Super-Girl to Captain Mar-Vell's Superman.
I feel like the reason this thread keeps veering back to discussions about how much leg Carol should show, is because ultimately, there isn't that much more to talk about with her. All that's being discussed is her potential / what should've been done with her in comics all of these years vs. What actually is.