I too have no interest in Korra as the Avatar. I watched her entire first book but had to give up a few episodes into her second season. She was simply unbearable. I would be willing to just skip ahead to this season had I not seen this description for the end of season 2:
Give her a second chance. These episodes show that she learned from her mistakes. The mistake made was giving her her abilities back at the end of the first season. She could have benefited from just being an Airbender for a while. And there was a perfect opportunity for her to get her abilities back when she reconnected with Rava after the Wan backstory. If she was only an Airbender then, and only Unalaq apparently believed in her being the Avatar without her bending the other elements, it would have instantly sold her on being a temporary bitch.
But she now understands why people hate her, and wants to do everything in her power to correct it. Any qualms with her character are completely addressed in these episodes, and while they're still slightly present, especially with the Earth Queen, they're very much justified whenever she goes back to her temperamental ways.