Good points about the meaning of “the people” and the ratification, parties to the compact, etc. “We the People” is lauded as a great achievement, but it really was the death knell of limited gubmint.
I'm not completely sure that's true. The states had the tools to maintain limited government, and they were not afraid of using them -- until it led to disunion.
One lesson I took away from Forrest McDonald's States' Rights and the Union was that once Andrew Jackson's particular flavor of federalism became the norm, disunion was inevitable. If it didn't happen over slavery, it would have happened over tax policy (tariffs) or central banking. Finding the balance in federalism was the main argument during the period between the ratification of the Constitution and the War Between the States. Once that war ended, federalism as created by the Framers was finished, and the new argument was how to use that all-powerful central government. Thus Progressivism.
The 14th Amendment inserted Roman Law into a document based on English Common Law, and the 16th and 17th Amendments were the logical outcomes of a consolidated union.
What I find intruiging today is that the 10th Amendment has taken on a new life, and issues that were supposedly decided in 1865 have been reopened for discussion.