A list of worst to best. I'll start:(worst to best), Water/Spirits. Lot of good in both. Water introduces us to all these wonderful characters, and has stand out episodes like The Southern Air Temple, The Storm, The Blue Spirit and The Siege of the North. Is dragged down by the (relative) lack of moral amiguity, some issues in pacing, and The Great Divide. Spirits is, imo, kind of underrated; it has Wan, Bumi, Jinora and Varrick. Beginnings is probably my favourite episode in the whole series. I also actually like Aang not being an excellent dad, and thought they dealt with it well. On the other hand, some characters are very out of character, Unalaq isn't much of a character, and the ending is pretty strange. 77/100 for both.
Air; I really like Amon, and most of our main characters, especially Asami, here. Main issues are the romance, and the Equalists. They aren't as sympathetic as they should be-remember when those people not even wearing the uniforms were cheering as Tenzin and his kids were brought out? I honestly lost most sympathy for them there. Yeah, they deserve help, but if they're going to be so malicious, they deserve punishment too. Rest is very good-83/100. Balance. Big jump up here. Old Toph was awesome, the feeling of unease about the Earth Empire, and Korra's character development were great too. Ending was very good. Only complaints are so little of the Fire Nation, and I didn't like the spirit mech. (Shudders). 86/100. Earth. Just great all round-I especially enjoyed the swamp, and tales of ba sing se-and that ending was excitingly terrifying. 92/100. Change. The best of Korra. The Red Lotus have such a wonderful humanising factor when they interact, and are truly menacing in combat. Korra has more or less learned her lesson here, and it's great to see her get it. Old Zuko, in my opinion, was handled pretty well-The North Pole weakens firebending, after all! The new airbenders dynamic was fascinating as well!94/100.
Fire. Not always as elegantly woven as Earth,(although the difference is not at all as much as some people say) but man, it just felt so satisfying. Zuko with the team is just wonderful, all of those episodes are just wonderful, and Azula's and Ozai's downfall are tragic and epic, respectively. I have only two complaints:the deux ex machina Rock, and the group never find out how Zuko got his scar. Standouts;The Awakening, Sokka's master, The Boling Rock..oh, all of them really. 96/100. What do you think?