I wonder why people hated this show its really good. I just didn't like how it focused in a lot of machinery but still its a good show. I love how they decided to bring some of the old characters and bring new characters. Season 1 was good, season 2 was meh, season 3 was HOLY GOD IT'S SO GOOD, and season four was great.
Here are my reasons: (spoiler alert)
Season 1 was good because it did bring back blood bending and we got to see Aang again but for a bit. It made me cringe a bit tho with the relationship things. Mostly episode 5. still its a good season
Season 2 was a meh because it was boring in the beginning. But throughout the season. it started getting interesting. But the ending wasn't the best and it had a lot of non-filler episodes. It didn't do much for this show so it goes with a meh.
Season 3 was the best and i have to admit better then the season 3 of ATLA. It finally gets to a lot of interesting parts, and it's more darker which made it better for me. There were Non-filler episodes but its still the BEST SEASON. I love how the Earth benders can lava bend and We got to see Lin's backstory with Su. Su is a good character and Opal is a good character and Zaheer and his gang is coooool. We got Combustion bending back and I think it was cool. the last episode was good and kinda creepy which I'm into. So far this is the best season in this show
Season 4 was great, better than season 1 and 2 but just less better then season 3. It was improving but this season went kinda down for me. It wasn't interesting like season 3 and more Machines were in this season. The first episodes were good but in the middle it wasn't the best but the ending was cool. I don't have much to say about this season so yea that's it
So maybe you should just skip to season 3 because season 2 and 1 don't add much. You should watch this if you haven't, because it's really not that bad....