the problem is not that they tried to make korra likeable, azula isnt likeable, she is a major bitch, but i dont see people complaining about book 2. nah, the main problem with book 4 is that, they had no idea what they wanted to do.
the story has no pacing, it goes all over the place, they winged HARD, and it failed because of that. seriously, we go from one training to the next, korra sometimes gets trapped and abused, again, out of nowhere, we kinda manipulate her, and somehow in the end she decides "i guess im a whore now".
its so badly done, even some dialogue scenes remain the same even after she "give herself to us", like the shake, a very easily edit when we joke "there jizz in it" she still barf it out, when all they needed was to just cut that scene out and make her say something like "i know" before drinking the rest.
people get too hung up on "i hate korra and so should you" to even judge things on their own merit(or in Book 4's case, flaws)...