Sakura is the manga's heroine. She was the one present for the final arc and the one that helped bring Naruto and Sasuke home. From the way he speaks, Kishi considered switching due to popularity but didn't because he likes Sakura more.
Hinata has done nothing worth praising. If she's a heroine, it's in the anime. What Kishi has been saying lately about Hinata / NaruHina, it looks like he doesn't care if Hinata / NaruHina burn. Nothing he has said lately is good for Hinata / NaruHina. I hope the trend continues.
The best part is to watch the Hinata / NaruHina fandom scramble. There is no defending this, yet they insist. I've seen them compare Neji's death with Itachi and Jiraiya too. What the hell.
I'm sorry to burst their bubble, but no Neji's death did not have the same impact as Jiraiya and Itachi. It could have been executed much better, and quite honestly this is why I preferred Obito's death compared to Neji. See when it came to Obito there was build up leading to his death,while Neji's just came out of nowhere. Granted shock value is good, but only if it's done right and Neji's death should've been done much better than how Kishi portrayed it. Besides the other reason why Obito had a bigger impact to his death is that he didn't die for a pairing.
You know the funny thing is I told a couple of NaruHina fans at college to tell me what do we know about Hinata in Part 2? They told me "well Hinata loves Naruto and she's always been there for him." Then I said "Okay do we know what her relationship is like with her sister? Her father? Her Clan? or what she's accomplished to become a clan leader?" and they quickly answered with "Well that's easy Hinata... uhh well...." and I was like "go on" and their response was "The Last of course everything will be answered there. We will know everything about Hinata's relationship with her clan, sister and father at that point?" and I said this "A piece of kitten movie to retcon everything in the manga for NaruHina to happen. You think that's gonna answer those questions."
Their last explanation was "You're just a hater who doesn't know good writing with good romance. NaruHina has that, all NaruSaku has is an abusive relationship where Sakura scolds Naruto for his stupidity that's not healthy. Hinata is so kind and gentle and let's Naruto do whatever he thinks is right."
Before I walked off I told them, "I'm sorry Sakura knows when to prove him for what he's doing. Your little princess in Part 2 would just be nothing but a house wife at home waiting to sleep with Naruto and that's it."
After that they were just silent , and I was smirking the whole time as I left.