I'd like to see that, too, but with no exemptions, exceptions, deductions, nothing but 10%. It would be in place of the current tax. Of course, an awful lot of government employees, tax prep people, lawyers, etc. wouldn't like that.
I would distrust a new kind of tax, such as a national sales tax. Odds are, we would end up with both things, an income tax and a national sales tax.
Reality is, of course, that the real reason the tax code is structured as it is, is so that Congress can control the behavior of American citizens. That power will never be given up.