If you think about it, Kishi likes to set up most villains as parallels to Naruto. What he could've ended up like if things were just a little bit different.
First, there's Sasuke. He's Naruto's parallel in the sense of being an orphan and not having a family at all. Sasuke cares about nothing but revenge, first on Itachi, then on the elders, and now on Konoha, for what happened to his clan. Naruto started out hating the village too, so he could've ended up the same way. Sasuke is what Naruto could've become if he let revenge consume him.
Then, there's Gaara. He's Naruto's parallel in the sense that he also had a tailed beast inside him, and was isolated/treated horribly by his village because of it. Dude had no one that cared about him. He ended up hating everybody and becoming a serial killer, though he reformed later. Gaara is what Naruto could've become if he became consumed by hatred and failed to find anyone that cared about him.
Then we have Nagato/Pain. He's Naruto's parallel in the sense that they're both students of Jiraiya, both members of the Uzumaki Clan, and both wanted to bring peace to the world. Nagato is what Naruto could've become if he lost his faith in people and gave up on the idea of there ever being true peace.
Looks like Tobi/Obito will be Naruto's final parallel. It's hard to say exactly what it'll be, but it seems like Obito is what Naruto would be like if he completely gave up on his hopes and dreams, and on the world in general. Tobi considers the entire world worthless and wants to create a dream world.