You can tell me many things, but you can't tell me Zuko isn't the best character in Avatar the Last Airbender. He literally had it all. Good backstory, good development, good design, good redemption. Sibling Rivalry with his sister. A badass Scar.
He's got a really good redemption arc though ye, and one that's very successful and doesn't feel forced. That's a thing l'd love to see more often in media tbh. We don't oft get quality Redemtpion arcs.