The ONLY realistic alternative is the FairTax!
Above all else, we must insist that there BE NO hybrid system! We MUST abolish the income tax completely, and do an orderly wind down of the IRS. Transition issues can be worked out.
If we are smart enough to go to the moon, and build a space station, we are smart enough to replace the income tax with the FairTax and abolish the IRS without causing the country to collapse!