The problem is when a fanfic writer turns a character into something they've never been in an ultra negative light, and the other main character is portayed as being victimized by said character, you're no longer writing the characters who's names you attach it, but an original story. I would suggest removing the Naruto characters names and turning it into your own original story. Change the names and the setting to whatever town you live in, bring in local elements and go with your story that way.
This is what I try to follow in writing fanfic, (a friend of mine, who professionally writes stories about other people's characters, also follows this): Write the characters as close as possible to canon, build depth from that, don't contradict character's canon personality, especially in a negative light. Even if you don't particularly like the character, even with villian characters, try to keep them in canon and don't make them worse than they were. Don't turn the characters into saints either. The best bet is portray them as in canon. For villians, definitely don't turn them into saints, but touching on some element from their childhood that makes the readers have a bit of sympathy for them is a good idea (note how Kishimoto will do this- even with Orochimaru, we saw how as a young child he missed his parents, ditto with Sasori, etc..), it rounds out the character.
I agree with those points your friend made. However some deviation is necessary in fanfiction, and one change can bring more, which brings out more deviation. The challenge then is to find a good point between straight canon and OOC-land, because going too far with the changing means you might as well not write about Naruto at all.
I missed with this one; it took off on me. While I think that it's theoretically possible to write a story bringing them to the conditions above it's neither in my ability or interest to do so, so no I won't be continuing that version of Whirlpool.
It taught me a lesson though; if I plan to go that far into right field to stretch characters, I better have a damn good explanation for it first. A drabble thread is not the place to do it.
In the interest of playing Devil's Advocate, a tiny story first:
I was in a high school Honors English class. We were watching Centennial, a movie/mini-series about America in the 1800s involving Manifest Destiny and all that. Since it was English class, the teacher was always about allegories, imagery, and metaphors in writing. (For all of you who've ever written "Man vs. Nature" on the page of your copy of Moby kitten? Yeah, that.)
As we were watching a Bald Eagle fly across the screen I turned to my friend and said, "Don't you think we read too much into this stuff sometimes?"
He replied, "As long as they <the director/producer/author> don't say anything I think it's okay to see whatever you want."Folks, that stuck with me. The reason I bring that up is without Kishimoto saying 'NaruSaku FTW' it's okay to believe whatever you want within reason. Otherwise why would there be so many debates still: NaruSaku vs. NaruHina vs. NaruSasu (ick. alright, no, there's no canon justification for this one outside of the squeeing of Yaoi fangirls. i'm just saying it's there)
Don't get me wrong, I can't really defend this one. I don't expect anyone to defend it for me and I'm on the wrong site if I did expect it

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Two more things:
1> I am curious, how did it make you feel though? Sad, depressed, confused because 'WTF that's not Sakura,' pissed off at Sakura, pissed off at me for writing her that way, pissed off enough to make you punch the monitor (please don't)? That applies to anyone who read it, btw.
2> If a different bunny for Whirlpool ever pops into my head, I'll replace it.
NINJA EDIT: 3> (So I lied about two.) I really wish I could write this amount of words this quickly for these drabbles... I'd've been done ages ago. :/