It sounds like a good idea, but the problem is figuring the "income". That in and of itself is what comprises the vast majority of tax forms.
Because of that, I prefer a flat sales tax on EVERYTHING, no exceptions whatsoever, services, goods, investments, real estate, rent, stocks, bonds, futures, options and the like. With all that in the mix, the rate ought to be around 7%.
Progressives do have that problem, because the basis for their religion is emotion over reason. ( it's the way of the neo-marxist. Dialectic materialism is the art of arguing falsehoods into reality. See hundreds of millions murdered in China, & the USSR alone )
Old School Liberals, ( like me ) don't have that problem because we have reasoned arguments for our causes. Sometimes we're even right.
Like "women should have the same rights as men". I hold that opinion. I am aware we are different, ( YEA! ) and understand that not being the property of father and husband have consequences. ( like not being anyones responsibility after adulthood. Root, hog, or die )
Sometimes, when my opinions differ from Blake, we find a common place where we can agree, and agree that the part we can't agree... well, we aren't going to convince the other on THAT point, and leave it as is. Disagree, but respect. ( if he thinks I'm nuts on the subject, he's at least polite about not mentioning my mother. )
On this subject, I certainly don't have THE answer. It's obvious to ME that spending far more than you make has a limited lifespan. ( ask my credit card companies )
It's historical fact that tax cuts bring in more revenue, longer, than tax increases. ( Bill Clinton's tax hikes brought in a LOT of money. But the effect on the economy was to cause a recession the last year of his office, cutting revenues, and leaving the next guy with the problem. History may not repeat, but it rhymes )