Housing and healthcare are essential for survival. If anyone doesn't get those things because they can't afford them, while others have far more than they need, that's cruel and unjust. You should include both of them under "assistance for less fortunate".
Schools have more benefits than I can list here. It's absurd to not fund them.
Culture attracts people to spend money in your city, which benefits business owners and many laborers, and generates a lot of tax revenue. Usually that brings in a lot more money than it costs, and that turns into extra money for essential services, instead of taking away from them. Sports can fall into this category as well, but those have gotten out of hand lately and sort of turned into a dick measuring contest between different cities.
I'm mostly with you on tax breaks, though. They're supposed to incentivise corporations to create jobs in your city instead of somewhere else, which should have a good ROI, but in practice it's almost inherently corrupt.
No one is preventing you from leaving the USA. Most countries are just making it difficult to enter. I'm all for having more open borders, but that's probably not what you're arguing for.
No one is preventing you from starting your own community either. There just isn't any land remaining that isn't already owned.
And the "punished based on the rules of the given community, or expelled" thing is describing a government, although because of the aforementioned lack of unowned land, they only expel immigrants nowadays.