The tenth amendment covers those things that should be left to the states.
"The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
Basically this one covers everything that the federal government should stay out of. People should govern themselves or the states should; the federal government should stay out of it. This is a debate between the Democrats and Republicans in many cases. One side wants more government control while the other wants less. There should be some common ground in this area, as what is best for the people may be different depending on each situation. No, I don't think the government needs to know everything I do always, but I do think that some consistency throughout the states would be good. I am not a lawmaker, however, so I cannot decide which of these things are better to be left to states and which should be federal. There are cases for both. The fact of the matter is, the constitution says that somethings should be left alone.