One Piece, Magi: The Labyrinth of Magic Recommendations
They are both about a long journey to accomplish a certain goal. And both have long stroy arcs. And the characters in both anime have sad background stories.
Male protagonist embarks on an adventure and touches many lives on the way. Epic fight scenes and funny characters are abundant throughout both of these shows.
Probably the 2 biggest world-building shounen today.Whats the most important,Magi has that great adventure (like One piece) feeling that few shows have.And it also has very unique setting.
one piiece is famous for its big wold and i think magi is going in a very similar direction.
Both are about a person who is striving to be a king(although alibaba wasn't at first) while having help from comrades. Both animes also give importance to the power of friendship and continues improvement among the protagonists.