I'm sympathetic to your view, but you're about 80 years too late. Our Constitution is not the one the Founding Fathers adopted; it's been amended formally 27 times. The "amendment" that allows administrative agencies to make law was not a formal one--basically FDR bludgeoned the Supreme Court into ratifying agencies' legality during the New Deal. However, the Constitution is not just what's written on a piece of parchment, it's the organizing principle of our society, and therefore it is fair to say the New Deal ushered in a new Constitution that contemplates power residing in agencies with authority delegated from the legislature. Yale law prof Bruce Ackerman is the original exponent of this theory; he calls the New Deal a "constitutional moment," just like Reconstruction and the Civil Rights era.
In short, the constitutionality of administrative agencies has been settled for 80 years. They're at this point as American as apple pie. Heck, in some cases, agencies can actually "interpret" the law in a manner that is literally inconsistent with the congressionally-enacted statute. See Zuni Public School Dist. 89 v. Secretary of Education.
Any program which runs right is obsolete.