It is definitely easier to look at this the other way around, as you suggest. If we identify the proper role of government, then we quickly find that the large majority of government agencies, watchdogs, czars, departments and "halfway houses" (by which I mean organizations like the Federal Reserve and Freddie and Fannie) are completely in violation of government's role as a defender of individual rights.
By this standard, the government is established by its citizens to hold a legal monopoly on the use of physical force, to be used solely for the purpose of protecting its citizens from force and fraud initiated by other citizens. It is not there to be the country's nanny, to tell us what to eat, drink or when we can die, to educate, to meddle in the economy or to create economic monopolies which bar private enterprise from entering a field and doing an efficient job. Fields such as utilities, infrastructure, transportation security, education and so on should all be privatized as they do not fall within the scope of the government's proper role.
I believe this litmus test - asking whether an issue falls within the proper role of government - is extremely important today, and is a powerful razor to slice away most of the dizzying debates we suffer through on talk radio or TV talk shows. Debates over how to fix social security, Obamacare, the TSA patdowns, anchor babies, illegal immigration, anything to do with unions etc., can all be wiped out by simply checking the premise that these issues should even be in the government domain in the first place.