I saw somewhat that Oda-sensei once said that Bonney,Vivi,Law and Boa Hancock will have importance in the future and well,we got bonney’s arc, vivi is a D and her ancestor Lili is a major plot character ,law had and still will have some importance due to the Ope ope no mi (and I still believe that Boa will rescue him and bepo ) but we haven’t got much of Boa Hancock,some people say it’s because of her devil fruit but I think we will have a revelation that she was Garling’s slave ,since we are in the final saga most revelations have to do with important plot characters and for her if it’s not her devil fruit ,it’s probably that she was a slave of a important character and for me it’s Garling!! Art by me