IMHO, Established Law should only be overturned by the Amendment Process. This is how we reversed bad law in the past, and this is how our Founders set it up. To change it any other way would be Judicial Activism, no matter how we spin it.
Your reasoning is a bit off. You've fallen for the attitude that, indeed, the Constitution is what the Supreme Court says it is. Jefferson recognized that the entire concept of stare decisis was the way in which the Constitution would be ultimately undermined. He voiced his condemnation of the judiciary in general and of tje concept of stare decisis in particular in a letter to Monsieur A. Coray, October 31, 1823:
"At the establishment of our constitutions, the judiciary bodies were supposed to be the most helpless and harmless members of the government. Experience, however, soon showed in what way they were to become the most dangerous; that the insufficiency of the means provided for their removal gave them a freehold and irresponsibility in office; that their decisions, seeming to concern individual suitors only, pass silent and unheeded by the public at large; that these decisions, nevertheless, become law by precedent, sapping, by little and little, the foundations of the constitution, and working its change by construction, before any one has perceived that that invisible and helpless worm has been busily employed in consuming its substance."
Your reasoning implies that an unConstitutional usurpation of federal authority becomes established law and that the only remedies left are either legislative, which, under current practice cannot overturn such decisions or Constitutional amendment. This would now apply to topics such as eminent domain under your criteria. Instead, it is possible that the Court, when presented with a case addressing a previous decision can acknowledge it's error and over-rule even long established law. This is what people envision happening with Roe. I don't disagree that it can also be undermined piecemeal, but I also contend that it is possible and permissible to overturn the entire decision. The liberals would claim it is activism. Instead, it is entirely in the realm of returning to the original intent of the document. To be activist would require creating new powers or rights not dealt with in the Constitution. Overturning Roe or Kelo or any of the myriad true activist Court decisions of the last 70 years on the basis that the authority for them never existed in the Constitution in the first place is a valid strategy. The key will not be in choosing future justices based on their "conservatism". A conservative justice implies an activist one, who makes decisions from a particular political viewpoint. The real criteria will be whether he or she is an originalist. If so, then their position on each and every social issue of the day becomes irrelevant. They will decide based on the document as it was written and understood, and if the authority is not in the document, then the decision is left to the states or to the people.