Of all the amendments in our current Constitution, if I were to just pick one, that I feel would be paramount to incorporate into a newer and improved version, would in my mind have to be the 2nd Amendment, but perhaps making its meaning even clearer as such:
This amendment to the Constitution grants to every American citizen the right to own, keep, and bear arms of any type and of any quantity. This right shall not be infringed upon or restricted in any way by the U.S. Government or any of its agencies or departments, by Congress, by any federal or state court or judge, or by any state legislature or state constitution.
It may not be as far-fetched as some think if the government keeps playing these kinds of games.