Technically, Runaways don't have a female leader for their first story arc.
She's not really a strong enough character to carry her own movie. It's not like she's ever carried her own book either. What would they even call the film? Photon? Pulsar? Spectrum? Rambeau? Certainly not Captain Marvel.
I respectfully disagree. There are a few characters who are strong enough to carry their own book who don't, Monica is certainly amongst them. So was Natasha until her recent movie related popularity. Naturally they'd call Moncia's film by her current codename
Spectrum, and use the current costume because it's awesome and unique and has an iconic feel. It's not like they shouldn't make a Carol movie because some people think she should be called Ms. Marvel.
Rambeau has a cool heroic background, as a sort of harbor cop, and action heroes have been made with less interesting and less original purviews. As far as I know, there are no other law enforcement superheroes on screen at the moment, making her angle unique amongst superheroes as well. Her powers are as original and interesting and cool as they come, honestly.
The only thing she doesn't have in spades is a supporting cast, and she does have a bit of one, this is mostly a result of her not having a solo book more than anything. The fact that she still kind of has one anyway makes her very interesting. She'd kind of the dominant/most popular figure in a few of the books she's been in recently. That's because she's a very strong character.
The supporting cast is a bit of a stretch. She already has some basic stock characters to build on, Harbor Patrol partner John Audain, childhood friend in need Professor Andre LeClare, shipping contact Ron Morgan, and mundane villainous ne'er-do-wells like dictator Ernesto Ramirez and scientist Felipe Picaro. All are important parts of her comics origin and should be included in some fashion. I would round it out with at least Marcus Daniels aka Blackout as the Yin (energy absorption) to her yang (energy creation) I might include Karla Sofen as well, but that wouldn't work as well without all the moonstone jazz that doesn't fit as well with Rambeau's origin. I would include Project Pegasus though. I would also, personally include a non-powered Patsy Walker as her good friend and maybe even a mysterious Jericho Drumm as a love interest. But that'd just be me.
Though... calling the move "Rambeau" would be hilarious on a few different levels.
