That's not at all true. She's a mother, who's fiercely protective of and surprisingly compassionate with her children, an interesting contrast to her hardass indifference with her colleagues. She's a very serious and competent professional, who constantly weighs her responsibilities as an incredibly intelligent scientist and an incredibly powerful superhero to determine which has a higher claim to her time and whether or not she owes the world the services of either. She's a selfish and impatient woman who carefully guards her reluctant but real affection and respect for her teammates, and is brusque and insecure about any acknowlegement of her genuine heroism. She's proud and self-reliant and nearly cripplingly afraid of the dark.
That's more depth than, say, Billy Batson's ever had. (Not that the Marvels need much depth; the simplicity of "a good kid who can become a good man" is a virtue in itself. Just saying, if he can carry a story, she's got more than enough to do the same.)