Personally, I feel like Su did not do the right thing. She deliberately turned her back on the earth kingdom when they actually needed someone like her to run it. The thing that irks me is that the writing has portrayed power with dictatorship, and we have Su spewing this repeatedly, fearing she'll force her ideologies on everyone. In actuality, there are some leaders who have power, and they do not force anything on anyone. This could have been her chance to change it..... and now she's irritated with Kuvira who actually took the opportunity to make it better (and succeeded at making the earth kingdom united).

^I agree.

While I'm not defending Kuvira's methods, she at least decided to act. Su was against it from the beginning, and looked down on Kuvira for wanting to help her nation. At the beginning, Kuvira wasn't even necessarily 'power hungry' she even encouraged Su to take action.

I understand her not wanting to force her ideologies on everyone, but she is confusing power with dictatorship. That didn't have to be how she ran things, it isn't always like that.

^ Exactly! Kuvira did remain loyal to Su, and then when Kuvira couldn't sit back anymore, Kuvira stepped up and decided to help. Su is being very hypocritical. She wants people in the earth kingdom to be happy and there be peace, yet when she is given the chance to bring that to the people, she acts like she cannot be bothered to do it.

I caught that with the writing too. That's completely teaching the wrong message. Power can sometimes be a good thing..... but this show continues to put it down.

I dunno, I think the show's not exactly condemning the good things Kuvira does, but saying it doesn't justify the bad things she does.
Personal fan theory of mine - loads of people last season were saying that guy in the circus photo of Su was Zaheer. Now, nothing came of that in the actual series and Su did fight him - but I like to think that they DID know each other many years ago and he influenced her ideologies surrounding freedom for individual people. Even though Su decided Zaheer had gone too far, she was reluctant to reign in the damage he caused because she wanted to see if the people of the Earth Kingdom WOULD in fact manage to sort things out and learn to govern themselves over the years, and was therefore reluctant to interfere. Not condoning it, or saying that it would have been a good decision for her to make, but I think that it would be pretty cool if this was the case.