The delivery might be intentional, she's not a human being.
I saw a Henry Cavill/Snyder interview with Kevin Smith where they kind of said the same thing, they didn't want Clark to be overly emotional because he's not a human being - his only fear is that he'll accidentally crush someone's spine, not that he'll hurt their feelings or his own.
Brie's a cool actress so maybe I'm a bit biased, but I can see it working.
I saw a Henry Cavill/Snyder interview with Kevin Smith where they kind of said the same thing, they didn't want Clark to be overly emotional because he's not a human being - his only fear is that he'll accidentally crush someone's spine, not that he'll hurt their feelings or his own.
Brie's a cool actress so maybe I'm a bit biased, but I can see it working.