This discussion is not about merely the "union of the states", nor is the context of any argument denying the recognized value then of that union.
They did not always assert that the union was the "best choice of liberty and freedom", but rather that it was the best choice at that time, and had severe caveats to that choice, even at that time, with the union being contingent upon the federal government being bound and limited to only certain enumerated powers, so as to protect individual rights and freedoms, along with state sovereignty, ... and even then, under those strict terms, the Constitution did not easily pass consensus.
There was not then any general recognition of the "concept of disunion to <only> to reset the union", and I believe what you're referring to is an idea advanced by Jefferson to 'reset' the laws <and constitution> of the country with every generation, something that only he advanced, and was profoundly rejected by Madison and others.
Furthermore, this nation is founded upon the principle of "separate little nations", and these being sovereign, not the federal government, and reserved the right to leave the union with that sovereignty, whenever the people should feel the need to withdraw. As shown, this concept was strongly supported by Madison, Randolph and other founders in both Ratification Statements, and state constitutions, and was not ever rejected at the time.
The Constitutional convention set out to reset the current Constitution. A reset was the entire point of the founders writing a new Constitution.