Speaking of Karin, I had a thought today. "What did Naruto's crush on Sakura begin?"
I felt like this question would never be answered, but then I remember the flashback where Karin developed her crush for Sasuke when they were younger even though there were no hints whatsoever that that happened back then.
Wouldn't it be interesting if someday, Kishi, the King of Flashbacks, has a small rewind of when Naruto fell for Sakura? It had to be when they were younger, before the original introduction of the manga. And we know they kinda all went to school together and whatnot. I just wonder how they first met and what was it like. Maybe it was before Sakura turned into a Sasuke fanboy?
Then again, when I write it out, it makes it seem more unlikely that this can ever come to be, so I guess it'll always be left to fanfiction. *sigh*
Also, I just wanted to say, could everyone use something other than mangareader when referencing manga pages? I can never see anything. It's a hassle to go to a manga reading website and look for the exact page, especially if the exact page is never specified, so the debate is lost to me.
Why does this seem less likely than the other flashbacks we've been given? Like you said, Kishi loves to use flashbacks in his stories, he has used them MANY, MANY times throughout his story. Especially in the war arc, even when they didn't seem necessary. We been given a flashback of how Karin got a crush on Sasuke, how Naruto and Sasuke first met, how Sakura and Ino became friends and later rivals, etc....
So far we haven't seen how Naruto first developed his crush on Sakura, all this time we just assume is because he thought she was pretty. That's probably true, but was there any other factors that played into it, was there something else he saw in her that he like? The same could be said about Sakura's crush on Sasuke, but that's safer to assume that it was purely for shallow reasons.
I see a flashback like that happening either when they have a mutual moment together, recollecting their time together (nothing too romantic, of course, it's still Naruto), or when Naruto confesses to her, and tells her how he originally felt about her. Neither may not happen though, and, like you said, a flashback between the two may never happen. But I don't think it is as unlikely as you say it is, because if any of us really expect them to get together, then it's not that far off to assume they will have moment together, and seeing flashbacks are quite common in the series, it doesn't seem that far off either to assume that a flashback of them first meeting may happen.