That's the problem with casting Captain Marvel.
They need one of those women who always seem 30 from 25 till 40 like Elizabeth Banks/Jessica Chastain/Rachel McAdams, but they need one of those in her late 20's/early 30's.
Chastain, for example, would've been literally perfect 10 years ago: good jaw and commanding chin without looking mannish, and still very pretty without looking like a 20-something girl, even when she was actually 20.
But now it's too late, since the movie won't come out until 2019, and the third avengers movie she'd be in would only come out in 2027 or whatever, in which she'd be past 50.
So they need to have the foresight of casting a demi-goddess before her powers manifest.