Funny you bring up that this is a Shonen manga, which is the one reason that NaruHina will NOT happen. Seems you don't understand how Shonen works, but whatever. First of all, Kishi is not going to go on this whole long romance thing where Naruto develops feelings for Hinata and declares his love for her eventually. It just will not happen, because as you said, this is Shonen. There is usually little romance in Shonen. Secondly, since this is Shonen, and it is targeted towards 10+ pre-teen/teen boys, the way Naruto has been written romance wise is how a boy thinks romance wise. Naruto wants the girl of his affection, who didn't acknowledge him, and he has to prove himself and do amazing feats/promises in hopes of making the girl like him back. He longs for the girl, and would do anything to get her, and in the end he does. Naruto is not just going to all of a sudden not love Sakura and develop feeling for Hinata for those two reasons. It would take to much romance to have Naruto all of a sudden not like Sakura and want Hinata, and that is not going to happen in a Shonen, and the other reason is Naruto likes Sakura, and that is not going to change for the whole trope thing I said before about pre-teen/teen boys.