Well, libertarianism, conventionally defined, is the philosophy that the only purpose of government is to protect individual rights. The conventional definition denies any mandate to further, or even the existence of the common good. You seem to affirm that government, on various levels, should further the common good, over and above protecting rights, so by conventional standards, you are not a libertarian. But, if you wish to call yourself such, no one's stopping you. At the end of the day it's just a label, and it's the substance of a philosophy, not its label, that is important.