Lately I've been feeling the the manga is too serious. To me it feels like the manga is going from one dire situation (Madara saying that he is going to Naruto that day) to philisophical discussions (about whether Bee and Naruto should be out in the front lines) back to dire situations (Kabuto almost capturing Bee, Naruto, and Shisui's eye). To me the constant feeling of doom is dampening the enjoyablility of the manga. So i think all of the fillers are good for the anime. They, for the most part, relax the seriousness.