As an overall answer: humans are incredibly adaptable, so as a person living in the US, it almost never subjectively feels bad. For goodness' sake, I knew people who lived in Chicago's Hyde Park (one of the most dangerous neighborhoods) and happily biked to work. I personally lived in what people would describe as a "hood" and a "third-world country" for a good year and a half, and honestly felt really safe over there. Because of this, I honestly don't think anyone can give an objective answer solely from their living experiences.
Objectively, the US is a developed country and is not terrible, but regarding your specific points:
Yes, the government passed shitty laws, and chose to not pass a lot of not-shitty laws.
Yes, there are more mass shootings than the country should have. I'm not going to say why.
Insured healthcare isn't expensive (correction: some stuff are still too expensive even after insurance). However, uninsured healthcare is incredibly expensive, and unfortunately people without employment/self-employed have to purchase their own insurance... which is also stupidly expensive. Also, a lot of things that should be insured aren't.
The different states are certainly different. US politics is very polarized, so heavy-blue and heavy-red states are quite different in their approaches to... many things in life. Whether they are good or bad is up to you.
I mean, people living in Switzerland complain about their countries all the time, even though almost everyone else in the world envy the way they live... so it is possible that some might be a bit overblown.