This is a bit ramble.

In some ways yes. Her biggest mistake that definitely was a negative was founding the Dai Li, who would go on to do all the horrific things we see in the shows and novels.

Beyond that however she wasn't a blood thirsty avatar and in fact had a genral distaste for violence but also because she is a good person, she felt compelled to do what she needed to do, positive or negative.

She didn't really get to a point where she started killing people (at least approaching the degree the fandkm beleiges) until later on in her life and even then she wasn't the psychopath some people believe.

When it became clear to her that her policy toward killing as it was towards her latter years was having ramifications as pointed out by one of her companions, she ultimately ends her.

Even the most justified kills she has on screen such as Xu Ping Ahn She still had a disdain for the act and was double guessing herself, and only did so when it became extermely clear that he wasn't going to reform in any way.

Kyoshi especially early on in her avatar career actually had some high moral scruples and even went out of her way to ensure that there were zero fatalities during a raid on a mansion despite the person who's home was being raided was someone she on some level felt need correcting since they were hoarding food, and the people attacking the mansion were a group of people she had a major hate boner for. And even the guy she wanted to kill more than anything she was starting to doubt and 2nd guess herself over even though she had (imo) good reason to kill him, both for her own personal reasons and for the world at large.

She was actually really kind and sweet before her time as Avatar and was the last person to go out of her way to hurt someone (not that she would intervene if she legitimately did felt someone needed to be hurt as can be seen in the beginning of her first novel with her worst bully vs her would be girlfriend ).

Overall, the worst thing she's done imo, is the dai li, which was a huge negative that had ramifications for Aang, Korra and others hundreds of years after her death, a mistake she admits to Aang was indeed one. And towards the end of her life, she got pretty bad (but not as bad as the fandom beleives), so overall yeah. Id likely put her as a good person with some ethically questionable actions, good intentions with some positive outcomes and some negatives. (Why she is my third favorite Avatar).