(2) Maine's constitution guarantees the right of Maine's citizens to alter the structure of their state government. It nowhere mentions any authority for Maine to secede from the Union. Treason is nowhere contemplated in the document.
(3) Even if treason were contemplated in the Maine constitution, its subordination to federal review would remain operative.
You are making the argument that the Maine constitution's provision for government reform can be interpreted as permitting secession from the Union. It cannot. Even if this flawed interpretation were to be pressed by Maine's judiciary, it would be rejected in federal court.
You are further arguing that Maine can unilaterally declare secession from the Union without review by the federal government. It cannot, by the plain words of the US Constitution. You are likely unaware of this, but Maine is a pure federal creation: it was formed out of Massachusetts for the express purpose of strengthening federal policy. So, whether one goes by original intent, or strict construction, or a positivist interpretation of both Maine and federal law, no act of secession by Maine can prevail.
And I don't think I'm coming up with anything new. Far from it. All this information is well known to any student of federal law.
Also, what you are proposing is not freedom - you are proposing a theocracy enforced by roaming bands of self-appointed roughnecks.
Time will tell.