It’s different. Do not go into watching it with ATLA expectations.
1) Korea is the opposite of Aang. She has the fire nation drive and earth nation stubbornness. She is weak in the water nation spiritually for being a water bender but the story goes into that. She has trouble with air bending which is hard to understand. Fire would be the opposite of water and she should have struggled there. The writers Got a bit lazy on this point and wrote something to fit their narrative.
2) These are 4 different stories loosely tied together. They don’t mesh well from one to the other. They are fine by themselves but having fewer episodes somethings are forced together.
3) The story is darker with how characters are killed off.
4) Too much time is spent on Korras love triangle.
I gave it 3 stars as it is OK and there could have been better character development and writing. The look and feel is not as good ATLA but it still works.
Think of it this way. It is far superior to The movie adaptation of The Last Airbender. Now that was painful.