Another Great Idea for writers is to write about your character going against his or her stereotype.
1) Such as a strong agent who loves to read mushy hot romance novels. You can show the feminine side of an gent who is strong, tough and shows no femininity to those she works with. What happens when she is assigned to work with a new agent? One that ends up unveiling the inner feminine soft girly side of her that no one else sees?
2) Or have your nerdy character be just as good at street fighting as he or she is with academics.
These are just two examples of creating characters who go against their own stereotypes. This makes them believable and more intriguing to your readers. Gives them something refreshing to read. Something exciting to read compared to the usual more predictable stuff.