Some of you people in this thread are really special. And by special I mean "short, yellow bus" special. Look here's the question as I understand it, is/was Sasuke a bad guy? And should he be punished for his "crimes"? In my opinion anyone who answers these questions with a no, congratulations, you are a special person (see context above). Either that, or you're extremely delusional, take your pick. Sasuke WAS a bad guy for much of the series, there's no getting around that. And yes, he SHOULD be punished for his crimes in some form or fashion.
We can see this because of his various crimes that he committed, and yes, he did commit crimes! No matter what his childhood was like, that's no excuse. For those who are using the "he had a bad childhood" logic to defend him, let me ask you this, why didn't Naruto do the same? And if Naruto had done the same things Sasuke had, would you be defending him? Naruto DID have a messed up childhood, I would argue in someways he had it slightly worse, but as of yet he's never betrayed his comrades or defected from his village, he's never sided with an enemy of his village (Sasuke's done that TWICE), he's never assaulted leaders of other shinobi villages nor participated in the attempted kidnapping of relatives of said leaders (as Sasuke did with B).
Gaara as well, in fact I would argue that he's only one who's had a worse childhood than either Sasuke or Naruto. And for those of you who want to bring up Gaara's "crimes" in a retarded attempt to put him in the same category as Sasuke, let me ask you something. How does Gaara's participation in the Invasion of Konoha make him a bad guy? Was he not following orders from his village's leader? What he did was ENTIRELY different from what Sasuke has done, in effect he did what nearly any ninja would do, and that's follow orders. If you're gonna accuse him of "genocide", congratulations once again, you're a special person. Genocide involves the mass slaughtering of people, tell me where in the series have we EVER seen Gaara slaughtering people in droves? You can't, because we've never seen it because Gaara's never done it.
Bottom line, while Sasuke has seemingly changed after his hearing the truth from Itachi and Hashirama, the fact is that does not automatically pardon his earlier crimes. He'll still have to answer for them, or at least he should (but we know Kishimoto in his obsession with Sasuke isn't gonna allow that), and at the very least those deeds will bar him from even being considered for the position of Hokage. Especially considering Naruto's status as a hero, not only by Konoha itself, but even by the kage of the other villages.