Shanks is one of my favorite characters in One Piece. I strongly believe that he is the guiding figure throughout the series. He is a role model of a perfect pirate, with honor and valor, but also a sense of adventure and not afraid to steal or kill. Luffy has held him as a role model since the beginning of the series (which is one of the reasons we see him in the first chapter). But, I support the fact that Shanks is so important that we ONLY see him at very monumental pieces of the manga. One, when he recieves his first bounty, and later with Crocodile's defeat (after a huge-ass saga -_-). But even then, Shanks one panel entries have a profound effect on the One Piece audience since he is the background goal for Luffy and his crew. Shanks knows the Grand Line very well and has connections with many of the pirates, including his friend Mihawk.