You see Nathan what you are not considering is that the seceding state(s) will write a BRAND NEW Constitution that literally outlaws socialism, to do otherwise would be in contradiction of the secession.
Which you can more readily obtain at far less cost by reforming through Article V.
Let us assume that you can get voters somewhere to do away with Social Security and the rest of the welfare state thus creating a free-market paradise, presumably this new political entity will be so attractive that everybody will want to go there and when they do they will bring their values with them.
In the 1920s, Miami, Fort Lauderdale and Palm Beach were free-market areas but those who came to exploit the freedom soon turned them into what we have today just as they have done in northern Virginia. They will do the same despite your new Constitution because that is the nature of the eternal YING and Yang of political societies. One group always attempts to use government to enrich themselves at the cost of another. So geographical separation at best can provide only a temporary solution, but I have to concede the same is true of any Article V reform.
We gain freedom for a time and hand the defense of it to the next generation.