The best tax system ever:
Income tax is henceforth illegal.
A 10/10/10 sales tax is instated. 10% to the feds, 10% minimum to the state, 10% minimum local. Triple on tobacco, alcohol sales, half on the internet, excluding tobacco/alcohol.
Sales tax is paid on all imports. No cheatin'!
100% advertising tax, split evenly between all levels of government as well.
To be progressive, there would be a poverty-level tax rebate.(Everyone gets back the first few thousand they pay in these sales taxes)
While we're at it, let's do away with all airport security and seal the cockpit of every commercial plane off from the cabin, both physically and by communication. That'd save some government cash.
Let's also restructure the environmental budget to stop throwing money at "global warming" and start spending money efficently, to solve real problems caused on the environment.
Education will be restructed to be the major, shared burden of the local and state government with limited federal involvement. A new standardized test will replace the SAT and ACT AND the various tests used to determine school performance.
Military will likewise be the major responsibility of the federal government.
The welfare system will be put in a box, mailed to russia, put in a bigger box, mailed back to the US upside down, ran over with a semi, put through a car wash, and rocketed into the sun. We will instead set up government co-operatives that anyone is welcome to live and work at.
Schools will spend more time teaching proper information and skills and not obscure testing standards. Education will obviously not be involved in the sales tax.
I'd keep going, but my imaginary perfect USA economy has a date with an oil rig in Alaska.