Re: Sakura Haruno's possible character development.
Look, I think you did a good job piecing this together, but honestly... That she recognizes Mokuton means absolutely nothing. Hashirama was a legend, the founding father of Konoha. That Naruto doesn't think about it is, well, the obvious reason.. Hashirama, the founding father, only shinobi able to use mokuton (except Yamato, but he was unknown at the time due to ANBU association).
Any shinobi within Konoha knows him and knows his mokuton. Even Naruto, but he just never piece 1 and 1 together on that part. And that 2nd mizukage hint made me laugh, sorry it's no offense, but seeing that as a hint, I must give you some credit though, but I am sure you can find 1000 hints for anyting throughout the manga then..
Also " In the Team 7 which consisted in Yamato and Sai, Sakura was always associated with Yamato." Yeah she was the medical shinobi, so it was important to protect her, thus she worked with the captain. Besides there is another reason for this. Naruto is close range, sakura is close range. Sai is long range, Yamato is long range. This makes only 2 good pair-wise match-ups in the team. And obviously Yamato couldn't let Sai have responsibility for covering Sakura, we saw he even had suspicion on Sai, and when he wanted Sai to help Sakura, well we all remember..
All in all, good job, it was nice to read, and despite being far fetched some of it could make sense, but I don't really find much of it as solid proof, and a lot of the so-called signs are pretty far fetched.