The Ur-Fiery redhead, Mary-Kate Dannaher in John Ford's The Quiet Man. As another character puts it, "That red hair is no lie!" She tries to slug out John Wayne himself! Maureen O'Hara's finest Fiery Redhead hour.
Bortai, the redheaded Tartar princess played by Susan Hayward in the John Wayne flop The Conqueror.
Ginny Weasley from Harry Potter is a double subversion as she is usually soft spoken but:
Harry: Okay, so this morning I'm going to be putting you all though a few drills, just to set things straight... [Everybody keeps talking] Harry: Quiet, please! [Nobody listens to him] Ginny: SHUT IT! [Silence] Harry: ...thanks.
Henriette de Nevers is an understated but still adventurous redhead in the film version of La Reine Margot.
Gimli of Lord of the Rings has red hair with a matching beard as well as being quick-tempered. Well, the temper part is kinda obvious because he is a Dwarf. Same goes for his father Glóin in The Hobbit.
Spirited Ashley in Junebug is a midler and realistic version of this.