“Well regulated” at that time meant to be in good working order - as in a “well regulated” clock. Not to have a bunch of laws (regulations). There was no standing army - but all able men were to be able to grab their weapons of war at a moments notice.
You Sir have it right. That is exactly what “well regulated” meant in the late 18th Century.
Correct. And there are those that believe 1A’s “law respecting an establishment of religion” refers to law that shows respect for religion.