The Clown Prince of Crime
Super Freak
The bull fighting symbolism didn't come up as often in the book as it did in the film which is why I assume that people who haven't read the book might assume that it was bigger than it was, lol. In the book Duke Leto kept both a painting of his father (shown briefly in the movie) and the preserved head of the actual bull that killed him displayed at opposite ends of his dining hall as a constant reminder to never let your guard down with regard to potential assassination attempts and other dangers. Paul's grandfather fought bulls as a hobby but the implication was that he was killed by a bull after thinking he'd worn it out and turned his back on it to embrace the cheers of the crowd. So the painting and the head were constant reminders to never do any version of that.
At another point in the book those two objects speak to self awareness with regard to being able to determine whether you're the bull or the matador when going against another person. I think the movie did run with that in the Paul/Jamis duel like you mentioned with Jamis thinking he was the matador until realizing too late that it was the other way around.
Oh yeah, they kept showing that head in the movie. Maybe I should read the book.