The plan won't bring any relief for s-corps.
So, at the end of the day, the only thing this plan will do is screw small businesses and maybe help the largest of corporations.
Let me give you an example.
A company that grosses $200,000 and expenses off $160,000 will report $40,000 in net profit, which will put that corporation in the 15% tax bracket.
If you do away with deductions and those lost deductions amount to $10,000, then you've raised that companies taxes, because you just put that company into the 25% tax bracket. So, instead of paying $6,000 it will have to pay $7,500 + 25% of anything over $50,000.
It's not hard to see how this is going to hurt small businesses, once you learn how the system works.