Not saying Wano should have been Zoro's WCI, but for an arc so focused on the culture and people of Wano to not explore Zoro's character a little more is odd. The whole reason he became a bounty hunter was because he lost his way home and being a Wano could be a nice callback with feeling like's finally found his way back. Him now being a direct descendent of Ryuma and returning Shusui to Wano could have been a nice little side story but whatever I guess.