Come in with an open mind, and you just might love it. Do not expect it to be a 1:1 adaptation, and don't expect it to be better than the original because, in all honesty, nothing can.
Is the acting outstanding? Far from. But, most of the main cast, Ian Ousley and Dallas Liu to be specific, did impress me and I quite liked their performances.
Does the show have an exposition issue? Yes, a little bit. But if people can love the Percy Jackson show which was an exposition nightmare that was all tell no show, then they can tolerate ATLA's show AND tell.
The dialogue could be better. But luckily for the show, it doesn't need to solely rely on dialogue to do its storytelling; it shows a lot, it uses flashbacks to its advantage, and it has nuance.
What I love the most about the adaptation is the action. It is chef's kiss, and in my opinion, reminiscent of Marvel's golden age. The action is what I am watching the show for; I wanted to see how the bending would look in real life, and I am beyond just satisfied. Despite its flaws, this show has all my support, and I am giving it 4 stars as deserved, and an extra one because the producers are open-minded and welcome constructive criticism. In an era where film and tv show makers cannot stand any criticism, the ones who do deserve credit.