Not all heroes look the same. There’s been some rumblings that Dr. Marcus isn’t living up to her legacy. Warning: MASSIVE “Star Trek Into Darkness” spoilers!
She's a physicist.
Which means forging authentic looking Starfleet transfer documents to check up on her dad's sketchy behavior is child's play. Proactive child's play.
She doesn't take shit from Kirk.
Straight out the gate she's all "Hey remember how your slept with my friend and then forgot about her so she ran off to become a nurse? Oh you don't? How so like you."
She doesn't take sass from Spock.
Another science officer on the Enterprise equipped with all the parts Kirk prefers? Spock is having a Vulcan conniption. Carol Marcus gives zero fucks.
And she certainly doesn't stand for sexual harassment.*
*While this is definitely a gratuitous underwear scene, so was the one where Kirk was naked in bed with catgirl twins. The only difference is the Internet (sadly) isn't inundated with shirtless Chris Pine GIFS.