The Fed and the money supply.
I have previously posted that the Fed should be given command of most if not all instruments (from withholding taxes to the strategic oil reserves) that affect the money supply. Giving the Congress veto power would be fine: they are too ineffective to cause any harm.
The Fed should also be given control of the national debt limit and have line item veto power over all spending and taxation.
I realize that the Fed is not populated by geniuses and that in fact most of the people there are only marginally competent. They however generally sensible and largely not influenced by political considerations and most importantly willing to make hard decisions.
The Congress and the Executive are so handicapped by inapposite political considerations that they are useless in such matters.
The execution of bank regulation is clearly something they are not good at.
They should perhaps adopt the rules and the policies (at which they have admittedly been rather incompetent) but abdicate enforcement to the Treasury or some other executive department.