HOWEVER if I was king, I would do a few things to change how the Executive Branch of the US Government does business. The first would be to remove those departments that are not authorized by the Constitution and would return their functions to the individual states to manage as they saw fit.
Here is my breakdown:
Department of Agriculture: ELIMINATED - no more farm subsidies guys. Let the market dictate price and operate on a free, fair, system. Let Congress oversee disputes between the states on Agricultural matters in it role of regulating interstate commerce. We don't need a department to do that. Inspection standards would be transferred to the Department of Weights and Measures which would NOT be a Cabinet position, but rather a regulatory body as provided by the Constitution.
Department of Commerce: ELIMINATED - and replaced by an independent commission to advise the Executive and Legislative Branches of government on matters commercial. The commercial attaches now serving US Embassies would be retained and folded into the State Department's general function.
Department of Defense: RETAINED
Department of Education: ELIMINATED - there is no Congressional basis for this institution and the role of education would be remanded to the States, themselves.
Department of Energy: RETAINED - This nation's most pressing need is the development of alternative energy sources and the requirement that we wean ourselves from dependence on foreign oil. Though it's not Constitutionally mandated, there must be a NATIONAL effort in this direction so the cabinet position and department remains. There is also a national mandate to control and regulate nuclear power and protect nuclear materials.
Department of Health and Human Services: REDUCED - to an advisory panel and supporting staff, interfacing with the Centers for Disease Control, but reporting to the President.
Department of Homeland Security: ELIMINATED - As EVERYONE in the system realizes, it's a sad joke. This whole thing needs to be re-evaluated.
Department of Housing and Urban Development: ELIMINATED - and remanded to the States to decide how to handle these issues.
Department of the Interior: RETAINED - but vastly reduced in size to deal with Indian Affairs and other matters such as NAVIGABLE waterways, interfacing with the Army Corps of Engineers. All national parks would be remanded to the States.
Department of Labor: ELIMINATED - and the statistics function remanded to the Congressional Budget Office.
Department of State: RETAINED
Department of Transportation: REDUCED in size and function. The US Coast Guard would remain under Transportation.
Department of the Treasury: RETAINED
Department of Veteran's Affairs: ELIMINATED - and remanded to the Department of Defense
Attorney General: RETAINED