Mild spoilers:
This was just wonderful.
It is a joy to see so many wonderful parts of the original series in well-done live action. Of course, they couldn't perfectly recreate the original series episode by episode, so things are different this time.
Some of the original episodes are missing, some have been mixed together, all broken down and rebuilt to create a solid recreation of the Avatar story.
Some of the changes will be unwelcome to some, some will be well received. I think this retelling of the story did a disservice to king Bumi, but made Characters like Suki, Gyatso, and Zhao much more compelling and interesting. Hell, they even make Firelord Ozai sympathetic at times.
I also feel that the middle few episodes drop the ball a little bit, leading to a slightly tangled and lut-of-place narrative. There so much that needs to be established, while keeping the narrative within the same lines as the original. As such, some elements are mixed together in unsatisfying ways. That being said, the first two to three episodes were absolutely stellar and it sticks the landing.
The retelling of the original story is new, different, and sometimes a little awkward, but overall very well done.
And the performances! Gordon Cormier and Kiawentiio both do excellent jobs capturing their characters, but never really shine. Ian Ousley absolutely steals the show sometimes, giving masterful performance as Sokka and adding to the character. And Paul Sun-Hyung Lee and Dallas Liu both give absolutely wonderful perfomances as General Iroh and Prince Zuko, both fully capturing the nuances of their characters. And shout out to Ken Leung for bringing a new level of Charisma and Madness to admiral Zhao, a surprisingly entertaining interpretation of the character.
Watch this and enjoy it. Don't take it too seriously. It's not the original show, it's its own interpretation. And it's a lot of fun. It's wonderful to see the world of Avatar brought to life in this way, and I can't wait to see more.