You dont give here any explanation why nami and zoro are main protagonist, they are important to the story like all strewhats to help luffy achieve his dream but the story is not about them directly, its them getting their dreams come true because they joined luffy, zoro would not become wss if not luffy, sanji would not find all blue without luffy etc etc... therefore the protagonist is luffy who moves the story but his crew helps him, also it seems u trying to push and agenda with the zoro point, a lot of strewhats sacrificed stuff for luffy, zoro fought the yonko because he is a supernova not to move the plot forward that was luffy, killer and zoro do not have the same importance yet they both fought on rooftop