One of my all-time favorite mangas is Katekyo Hitman Reborn! Created by Akira Amano, Reborn! tells the story of Tsunayoshi Sawada (or Tsuna) and his reluctant involvement as the next head of the Vongola mafia family.
What I loved most about the manga was that it never forgot its origins and it stayed true to the characters established. Tsuna is ever the reluctant hero, constantly doubting his value and the position he holds with his friends, his 'family'.
Though he does develop, coming into his own as a powerful successor to the Vongola mafia family, he constantly laments the fact that he must participate at all. It is only upon Reborn's insistence and for the safety of his friends that Tsuna ever really acts. By the end of the manga, Tsuna is still adamantly refusing to step up as the new head of the family.
One of my favorite aspects of Hitman Reborn! is that is doesn't overstay its welcome. Comparative to mangas like Naruto and One Piece, which are long-running mangas (One Piece still ongoing), Hitman Reborn is short. It had a 409-chapter run, compiled into 42 volumes.
For comparison, One Piece currently has 792 chapters and Naruto finished with 700.
With such a short run, the manga doesn't have time to peter out or feel like it becomes redundant, something that I felt happened with Bleach. It knocked out the storylines it wanted to, answered the most pertinent questions raised by the narrative, and left the reader wanting more.
Ultimately, I do hope for more Reborn! i nthe future, though that seems unlikely.