If you read Naruto from the beginning, you will get a sense of great excitement in anticipation of the future of the series. There's Naruto who has a legendary uber-powerful monster sealed inside him, Sasuke whose clan was annihilated and wants revenge, Orochimaru who is nearly the best villain ever, Kakashi and Gai, Kabuto, Sandaime, legends of past awesome ninjas like the hokages and the how the story and characters are affected by them. Etc. etc.
However, Kishimoto fails to capitalize on this great beginning to his story and gets carried away. Everything up to Naruto vs Gaara can be said to be the best part of the series. With the start of Naruto chasing after Sasuke, the series start going downhill. At some point it gets ridiculous. Right up until Naruto vs Sasuke, I still very much enjoyed the series. The fights were awesome back then. Deep and exciting.
With the 2-year time-skip, the manga loses control altogether. Naruto's training with the legendary ninja Jiraiya only yields Oodama Rasengan that he uses once, that's all. And it drains him too. The story starts sucking majorly. Akatsuki is cool and all, but the story is crap. Orochimaru is forced into the sidelines and people less interesting than him get all attention. Sasuke powers up, so much so that Naruto may as well have been not training at all during the two years. I forget other details, but this time was boring as hell.
Akatsuki easily captures the bijuu that we were led to believe were truly formidable, almost invincible monsters with near unlimited chakra and stuff. And the people who caught them? Most of them don't have the kind of power needed to battle a capable jinchuuriki even 2 on 1. But they caught them anyway.
Battles in part 2 are really shallow and boring. Compared to the battles in part 1, in the chuunin exam and the Sasuke-chase, these battles don't even compare. Of course, power-wise it levels up, as shounen genre demands, but the content and depth does not match up.
Towards the end, Kishimoto finally went full senile. Manga became a total wreck. All the people of the past we thought of as awesome were brought back to life and their characters ruined. The images tarnished. Really! Orochimaru becomes a side character. Tobi turns out to be Obito, ruining Kakashi Gaiden. Sasuke comes back to fight the good fight. Oh boy. Madara comes back to life and single-handedly, with little effort wipes out the previous and current kages that we considered capable shinobi. The bijuu are less than toys before him. Obito becomes Sot6P, kinda, but becoming juubi jinchuuriki. He's OP, but still loses. Madara takes his place. Heck, even I'm getting confused writing this. Umm, oh yeah, the real Sot6P comes and gives Naruto and Sasuke new powers, they battle Madara. Madara is back-stabbed by Zetsu (!!!). Turns out Zetsu really works for Kaguya, Sot6P's mother(!). She tries to destroy everything after getting rid of Madara. Naruto and Sasuke, with Obito's help (!!) manage to beat her. gasp I need a break. Hmm, then Sasuke back-stabs Naruto (!!!!). They fight to a draw.
I give up. Kishimoto sucks.