Man you guys are just setting yourself up for mockery IMO. If Luffy is the literal reincarnation of Joy Boy, then Zoro may also be revealed to be the literal reincarnation of Ryuma.
It was pointed out at the start of his fight with King that he's the spitting image of Ryuma:
And he bears a near-identical appearance to him:
Furthermore, Oda has said in a One Piece magazine that a samurai that can be considered the second Ryuma may have already been born:
This Samurai is in all likelihood Zoro.
Furthermore, the body of Ryuma acknowledged Zoro and said that Shusui will surely be satisfied with Zoro as its master:
Zoro will also visit Ryuma's grave after the battle is over:
If Joy Boy and Luffy are likened to Naruto and Asura, then Zoro and Ryuma may be likened to Sasuke and Indra.
Arguing that Zoro's connection to Ryuma is completely unlike Luffy's to Joy Boy seems like fighting a losing battle to me.