There is some truth in what you say, but I think taking on Planned Parenthood strongly could help. Rand stood up to Obamatrade, and anti gun parts of the Patriot Act. He needs to start talking about this kind of stuff. Carson shot up in the polls and I don't recall him saying much hawkish in the debate.
Bottom line, talking about the 4th amendment isn't working for Rand. No, he shouldn't change his position, it just shouldn't be his main stump speech line anymore.
If abortion is the most important issue then there isn't any shortage of candidates that will go as extreme as they can on the issue, Huckabee literally wants to use the military.
Rand's only chance was to be a warrior against the establishment, he should of been blasting Neocons and GOP leadership the entire time instead of trying to buddy up to them. Rand's only chance was to double down as a libertarian, perception is reality and it didn''t matter how much pandering Rand did the establishment was never going to trust or support Rons son. All that matters is exciting the base, non-base voters get excited by excited base voters.