Otherwise, I agree with most of the substance of your comments but disagree with the extension of the militia to women. Nothing in the original Constitution prohibited women from voting, and many women voted in the late 1700's and early 1800's. In spite of women's exercise of this right at that time, the Founding Fathers did not see them as part of the militia. Men and women were created to occupy different roles in the home and in society. While women have used force to defend home and family during emergencies, military service is generally incompatible with the woman's role.
I make this point because I think your argument depends too much on the militia aspect of the Second Amendment. The part about the militia is an explanation for the main clause of the amendment, but the right to keep and bear arms does not depend on one's being in the militia. A writer whose name I've forgotten (maybe J. Neil Shulman or something similar) drew an analogy to illustrate this point very well. He asked what if the First Amendment were broken into parts and part of free press said this:
An educated electorate being necessary to the security of a free state, the right to own and read books shall not be infringed.
Would that mean that only people with a certain level of education would be allowed to own books? Would it mean that only those enrolled in classes and furthering their education would be allowed to own books? Would it mean that only school books or only recreational (sporting) books would be legal for average people to own? Would it mean that only registered voters, the electorate, could own books?
One could play with these questions for hours, but the point is the same. When we look at the same wording in a different context, we see that being in "a militia" is not necessary for one's right to own a gun to be protected.