Tired but getting through the day

The narrative already compares Sakura and Rin.

They're both the sole girl on Team Seven in a love triangle where she loves the emotionally closed-off and unattainable boy over the cheery dunce who crushes on her. Their appearances are somewhat similar: short hair parted in the middle with markings on their face, a medical apron around the waist, generally lithe looking. She and Rin share the same talents: not only are they healers, but they also have Water, Fire (Sakura develops this later, according to the anime), and Yang Release, and they're both resistant to genjutsu. Maybe Sakura's interest in healing, instead of being shoehorned in so that all three members of Team Seven could have Sannin mentors, could develop more naturally because her aunt had a talent for it that maybe her mother or another character could mention it, and young Sakura could become interested herself and read up on it, eventually developing a hero worship for Tsunade when she learns about her, hence why she goes to her directly at the end of Naruto's first part.

Their names are even interesting: Rin Nohara can mean Field Bracing Winter Air, while Sakura Haruno can mean Spring Field of Cherry Blossoms. Winter is often a symbolism of death, while spring is symbolised as life beginning anew. If we take Mebuki as being Rin's sister, it would be Mebuki Nohara, Field Sprouting/Shooting/Budding, and the word Mebuku usually symbolizes the end of winter and the beginning of a new phase, hence why she becomes Mebuki Haruno, a Spring Field.

Mebuki loses Rin to death, but gain Sakura in the new phase of her life when she is no longer a Nohara.

In fact, why do we never see Sakura's parents? Maybe they hate the ninja life. They certainly seem to prefer civilian life in the brief moments we see them in filler. By making Mebuki and Rin sisters, you could say that they were forced to conscript during the Third Shinobi War, and while Mebuki was talentless and relegated to doing grunt work as a Genin, Rin was talented, joined Team Seven and became a Chūnin, allowing her to go on more high-stakes missions—which as we know, leads to her death in a mission gone wrong.

And that could also be why Mebuki is so harsh on Sakura during Road to Ninja. While I am not excusing her cruel remarks (because why would you insult your daughter in front of other children and parents... scratch that, why would you insult your daughter period???), maybe she is trying, in her incredibly fucked up way, to discourage Sakura from pursuing the same path her sister took. Trying to protect her. Only she's pushing her away, and Sakura distances herself from her parents, rebels, and because of it and becomes the very thing that Mebuki feared but cannot do a thing about since her daughter is literally training under the Hokage. So, all she can do is make snide comments to deter her.

Also incredibly fucked up? Sakura's early attempts to look sweet and innocent. To hide the rougher aspects of her personality and act like an ideal girl. From what we see if Rin, she's incredibly kind, forgiving and gentle despite her profession as a ninja. Probably idealized memories, but imagine if Sakura had been trying to hide her real personality because her mother was pushing her to act more like he dead sister. That she wanted aspects of Rin to live on through her daughter, hence Sakura's "inner" personality manifesting.

And this would also "fix", for lack of a better term, her relationship with Kakashi.

Kakashi has always been more overprotective of Sakura, and yet also the most neglectful of her. He literally didn't train her during the 2.5 year time skip, and was completely unaware of the abilities she developed until the redid the bell test. For a man who preaches never abandoning comrades, it sure was shitty of him to neglect the remaining member of Team Seven while the other two were gone from the village.

By making Sakura Rin's niece, it would give more depth to his keeping away from her. Maybe he sees ghosts of old Team Seven in new Team Seven. He sees Obito (and his sensei) in Naruto, himself in Sasuke, and Rin in Sakura. He sees the dynamic all over again and is internally panicking. Fearing it will go down the same path. And as such, he'll step in always to protect her and try to keep her from harms way, but at the cost of neglecting her offensive training. Maybe he can't bear the fact he failed another Team Seven, and thinks keeping away will protect Sakura. Or maybe it's to avoid further trauma, who knows?

Maybe he and Mebuki can have an antagonistic relationship. I imagine Mebuki would HATE this man but can't do anything about it since again, the Hokage put together the teams.

Plus it would make her brief moments with Obito poignant. Imagine if while alone in the Kamui dimension with him, she hits him with "my mother said you were my aunt's best friend, I want to believe that the good she saw in you really is still there" or something.

And Sakura can have a character arc of growing as her own person, to be true to herself and branch out beyond healing and develop something unique from Rin (and Tsunade). To show that she's not Rin and will never be Rin. That she cannot be a replacement for what the people around her lost.

MAYBE SHE COULD EVEN MEET RIN SOMEHOW LIKE HOW NARUTO, KAKASHI AND SASUKE GOT TO SEE AND SPEAK WITH DEAD FAMILY MEMBERS ONE LAST TIME, AND HAVE A POIGNANT TALK WITH HER AUNT.

Yeah, anyway, those are my thoughts. It gives her a connection to the overall main plotline without taking away the fact she doesn't come from a clan (because I looked, and nowhere did it say that Nohara was a clan), and a character arc that just doesn't focus on her boys. Because the original manga had good bones with how Sakura mentioned she wanted to be out of Ino's shadow and be her own person, only to fumble by making her Tsunade 2.0 with nothing unique. I say we continue that arc by having Sakura's fears reinforced with the Rin connection, and her goal to become her own person and not just someone else's ghost.

Thank you for coming to my Ted Talk.