Would you suggest changing my nose like James Dean's or Brad Pitt's? What are their differences? (photos)

Surgery of the nose should be tailored to an individual's appearance, taking into account the surrounding facial feature that you have.  Trying to have surgery to look like a celebrity is not necessarily the right way to go about this process.   Seek the care of a board certified plastic surgeon with a 3D modeiling system such as Vectra 3d who can help illustrate changes that are specific to you.   

While both of these men are handsome and have great noses, you must be sure the nose fits your face!  Without pictures, it is hard to say.  If you would like to send photos, I can give you a better idea of what would benefit you!