How about neither. Both the RNC and minor parties have 'lacked success' from the liberty point of view of getting policy changed. I have suggested a third route many times, of growing the grassroots movement outside of any party structure, major or minor, just leverage the best of both. Draw from the principled, vetted liberty people in the LP/CP, and run them as liberty Republicans or liberty Democrats, mainly in primaries where there are open seats. Win the primary of the party the district leans towards, and coast on that inside track to victory in the election. That replaces the steep cliff with a takeable hill.