Look like mihawk might join shanks later on which set up the fight between shanks vs luffy and mihawk vs zoro. Or oda pull a twist and mihawk get captures off screen lol.
But I think we"ll probably see Shanks/Mihawk together soon:
"You know, Mihawk, with great power comes great Freedom. Gol D Roger called it "The human burden." Myself, I just call it as I see it: the responsibility of the master to discipline the servant."
Shanks looks directly at the camera.
"The fishmen, the okamas, the giants...It's our responsibility to civilize them. And if we can't? Then they shall dangle from the adam tree. The Day of the Rope is near, Mihawk. We'll have every fishman under the sea dead or in chains in 10 years, and may God have me lose my arm to a weak ass seaking this very night if I'm wrong. God bless the World Government Gorosei party."
"Shanks, did you know why I get to live in a castle for free? It's because of the humandrills. When human civilizations are peaceful, they mimic their neighbors and behave as docile pacifists. But in times of great war, they too become violent and aggressive - so much so that they managed to drive the people who lived here off their own homeland."
"In my opinion, the ((Gorosei)) are pretty much the opposite."