Interesting point. A lean toward libertarianism by the Republicans will make for interesting bedfellows, and will certainly alienate professional politicians from both parties who live by making government bigger in exchange for campaign cash (i.e., robbing Peter to pay Paul).
Suppose Cruz is the one who will lead the new, limited-government movement. It can't be seen as simply a backlash against the errors of the Obamites; it must have principles of its own. To start the list of these principles, I suggest the reformers pledge strict allegiance to the Constitution. And then amend the Constitution to implement 12-year lifetime term limits for Congress.