RubyRedRhapsody
I mean... Snape is a jerk through most of the books, and yet he is a beloved and deep character. But that doesn't mean that I think that Harry and Hermione and whoever else are dumb as dirt. All it means is that I like Snape.
They are sometimes.
Plus, Snape wasn't really a jerk; he was cranky and overly teachery. His actions were perfectly understandable and technically 'unmean' from book one. He saved Harry from a spell during Quidditch.
Zuko was similar. What he did was understandable, as was where he got his prissiness (explained rather early in the series). He was very loyal to his men, and several times aided them or Iroh instead of taking ignoring them or taking advantage of their plight to further his own means.
Both did something they thought they wanted or needed--Zuko allied with Azula and Snape with the Death Eaters-- and worked to redeem themselves of those decisions.
By the way, did Harry ever apologize for his dad and the others he looked up to as heroes for being such jerks to Snape? I know Harry didn't do it, but he does take after and hang out with the people who ruined the life of someone who saved his life.