I Want to Believe That Sasuke Could Be A Hero, but.......
I think that Sasuke is an amazing character. He is the perfect character full of twists and turns. While many people can't stand him, you can NOT deny that he is a fantastic character.
I can definitely see Sasuke becoming a hero, either as a sacrifice or a Deus ex machina (That's a technical term for a last minute save that could be predicted but was not hinted at.) But as much as I want that to happen and believe it would happen, Kishimoto himself has hinted at him that Sasuke will be the final villian.
Here is the interview:
Jump festa Kishimoto interview 2010:
Kishimoto: Sasuke's becoming more and more evil, and him fighting with Naruto will probably be the last event
Jump festa 2012 Kishimoto interview:
Question: What is going to happen to Sasuke next year?
Kishimoto: There is still much story behind Sasuke. His appearance will be more frequent next year.
Question: Has it been fixed from the start that Sasuke should leave the village to be what he is now?
Kishimoto: “Yes its from the start. There were the same old stories in which an enemy turns to a friend and I wanted to write a story where an once friend becomes an enemy.”
So, ultimately, maybe Sasuke will be a "Hero" in some way, shape, or form. But I do not believe that it will be anytime soon but rather when he becomes much more evil. Everybody loves a redemption story, and as evil and deranged as Sasuke is, if he somehow turned good again, would it truly be a big redemption? He hasn't done a whole lot of evil....yet. Something major is going to happen to have the entirety of the shinobi alliance hate him.