He should simply go to the Fair Tax, with a limited transition phase. At least, he's bringing the abominable situation of the present tax code to the fight.
I agree. The Fair Tax would work much better than the mess we have now.
As for fixing his plan, ditto, he has said all along it's a blueprint. As least he's working on it and not following the Pelosi method of 'pass the thing, then read it'.