Good chances that eventually Zoro will have to make his own black blade in order to rival Mihawk. Or at least I like this idea. This could also be a reason why Oda decided to have Zoro leave Shusui in Wano (his former black blade, Ryuma sword). But since he didn't even bother to have a Zoro-Ryuma moment like Zoro visiting his grave at the end of Wano I doubt Oda will do something "so focused" like this and instead just bring out another power up mid fight like usual.