Considering the "good bye" Weekly Shonen Jump gave HxH before the last hiatus. This one smells to me like it was Shueshia who begged Togashi to publish in WSJ because they are thin as hell with their series given than most of the hit ones are finishing, ended or are in the Jump+ app nowadays.
More than likely. Outside One Piece, they don't have any heavy hitters right now. Sakamoto Days, Kaguarabachi and Blue Box are their tier two popularity ones. All of these could blow up once their respective anime comes out. Though I am concerned about Sakamoto's anime in comparison to the anime. Obviously Kagurabachi needs more chapters to mention its anime.
I prob will start reading One Piece next year. But series like Akane-banshi and The Elusive Samurai are IMO the 2 best series in the magazine, but those types of series don't really become a heavy hitter, though.