For me, season 1 as a whole felt super rushed, and I absolutely HATED the ending. So much that I raged and ranted about it for weeks. That deus ex machina at the super end bit annoyed me so much. It almost ruined the entire finale for me, actually. I hate unjustified deus ex machina--and there are some instances of d ex m that are completely justified in my opinion (Aang's gaining of energy bending from the Lionturtle being one of them), but Spirit Aang showing up out of nowhere and giving Korra this ability without making her work for it (and returning all her bending and giving her mastery over the Avatar State all at the same time) is what really pissed me off. At least Aang had to work for his d ex m save-the-day-power. Korra just got it handed to her free of charge the first time she was able to actually contact a past life. All of these things are the reason why the last three-five minutes of the first season almost ruined the finale in my humble opinion.
 
The handling of the love rectangle (because that's what it was for a good portion of the season) also really bothered me, as well as the fact that Bolin's part in it was played completely for laughs and I thought that, despite him being mostly a comic relief character in the first season, he could have had really good development and rounding out if they'd treated his heartbreak more seriously.
 
Also, I feel like the pro-bending subplot was not very well balanced with the main plot of the Equalists and trying to learn how to defeat Amon and learn airbending. At times, it felt like pro-bending was the only thing that was important, when it was totally not all. I know it was a cramped miniseries (not knowing until late in the development process that there would be more seasons), but I still feel like they could have balanced it better and given proper weight where it was needed.
 
All these put together are why I liked season 2 so much more. I mentioned in my last post that I have fewer problems with the season's content and storytelling method, and the problems I do have I don't consider to be as burdensome or annoying as in season 1. Also, Bryke took a lot of risks with their mythos, bringing in the tale of the first Avatar and Harmonic Convergence and Unaloq's final goal. So many risks that I can't not admire them for it. Risk-taking is often make-or-break when telling stories, so the fact that they did so much of it won a lot of respect from me, and well-deserved, since I feel that their riskiness made sense within the context of the world and did really interesting things with the characters, and developed them a lot more than I was expecting and in ways I never saw coming. I absolutely loved the role that Jinora played in the finale. If she keeps being awesome like that, she might make it into my favorite character list. Also, I really enjoyed the animation bump that season 2 had, as well as the increased quality in background illustration. I think artistically, season 2 was a big improvement on season 1.