if you think zoro and sanji has been portrayed in a more valuable way then idk what to tell you. Luffy did not let zoro fight a swordsman in Issho and sanji could not save luffy without being saved by germa. Sanji is supposed to be fast.
Zoro has incredible portrayal himself and will most likely end up as the counter part and Luffy's moon. The hints are strong with this one too. So stop the cope.
@shanksisevil111 let's not make it sound like you can achieve shit in the world of One Piece without being born this way. If you are not born as a conqueror, you are out immediately. The fight for the throne is decided by those conquerors, that was said years ago, and powerful Devil Fruits are also gifted. Or the fact that Blackbeard can consume several Devil Fruits.
Luffy was never portrayed as achieving everything with solely hard work. Though the thing is, he does work hard, he has incredible will, while also having additional advantages since birth. The fact that he ate the Gomu Gomu no Mi was precisely because Luffy's ambition and character attracted this power. Hence Shanks also sacrificed his arm for Luffy, witnessing how his words matched Roger's.
And I think as soon as Joyboy was introduced namely, it was pretty clear that Luffy will continue in his footsteps. I don't think Luffy literally became Joyboy though. We know from Sabo that you can inherit the will of the previous user of a fruit. We know objects inherit the will of the previous user too.
But in the end it is obvious that everything is more or less destiny. That's why Buggy isn't the next Pirate King. Because no amount of hard work will help him.