How Great Would it Have Been...(Narnia)?

How great would it have been, in Prince Caspian, if Susan and Peter hadn't been siblings? I mean, this might be totally ridiculous, but I thought the fact that Caspian and Peter fought was one of the most amusing parts of the movies. Talk about serious man-pride problems. lol Anyway, I just thought it would have been funny if they had another thing to fight over...AKA Susan. *shrug* What would you have liked in the movie? I'd also kind of rather it if Susan didn't become anti-Narnia in the future. It's rather unfortunate, actually. She's probably my favorite of the four children.