I have long believed that Kuzan will ally with Shanks. That he will switch sides when the battle between Redhair Pirates and Blackbeard Pirates starts. Both are laid back guys, who lost limbs, were in high World Government positions and saw the evil of that entity. There is no Titanic Captain for Kuzan to face, I think he will fight future BB ally Kid instead. Saul is on Elbaf. If BBP vs RHP takes place there, Saul might try to help the Redhair Pirates, perhaps he fights Wolf. Kuzan would reunite with his old friend, by switching sides. It has to take place on Elbaf, for Pizarro to take full advantage of his fruit. He could wield the giant sword. No island compares to Elbaf.