And the rich do pay a higher percentage of their income in taxes than the non rich.
No. First off, the rich pay only their special 15% rate. And the non-rich have their entire incomes subject to to sales and FICA taxes. How much of his income did Romney pay in sales taxes last year?
The rich still pay more, taking all of that into consideration on average (including the regressive sales tax - which is not a federal tax anyway of course). Sure if some guy just gets dividends, and has no taxable interest or earned income, the federal rate is 15%, bearing in mind that the income was already taxed once at 35% or whatever at the corporate level. FICA is meant to be sort of a pension plan, where what you put in, reflects what you get out, with means tested cross subsidies. To dump the FICA tax would put a particular burden on earned income, as opposed to unearned income, which is not wise in my opinion. If you want to soak the rich some more, get rid of a bunch of deductions on a means tested basis, and raise the rates if you have to.