Very well said, especially your last line--a very important point to remember.
I do question your interpretation of the 2nd Amnd. to be "the right to keep and bear military small arms". I think the way it was written using just the term "arms" with nothing defining or specifying the type of arms, the word "arms" was used as a general, all-encompassing term. There were cannon as well as muskets at the time the Bill of Rights was written, and even though it was probably expected that most individuals would not own a cannon, it wasn't forbidden to them either. As a general term, I think 'arms' applied to whatever was, or would be, state of the art weaponry, and it was left to individuals to determine what would suit their needs and wallets.