Hello Kettlebelles, this might have been covered, I only read your first message
"I'm not telling you how much tax we actually pay but in the US the percentage would be way lower. It's quite tempting."
I lived in Chicago and paid significantly more income tax there, earning the same income, than in the UK. HMRC actually refunded a significant amount for the first and last year where parts of the year had earnings in one and then the other country. Also, in the US, tax credits/deductions will be included in your return whereas in the UK many people receive in work benefits but would not consider this effectively a deduction from their income tax.
In the US I found above a certain income (and therefore a certain lifestyle) the cost of living is less than in the UK. However vegetables and utilities were much more expensive, the cost of accommodation starts higher than the UK at the lower end but then gets relatively cheaper. So, if you're not rich you pay a significantly higher proportion of your income, on most necessities, than in the UK.
I really loved living in the US but would not stay long term.
If you are young (and will not age), childless (and will not have children), healthy (and invincible), have no use for the justice system (and never will) and have a high income (that is guaranteed for life) then go for it.
If you do decide to stay in the UK then doing research, voting, campaigning and maybe paying a bit more tax is probably more likely to get you what you're looking for.