I held off from answering this one because it’s so… difficult.
On one hand, the Constitution was written in a different era, with different [but not that much] circumstances and technologies. In that respect, our Constitution should pertain to the current times.
On the other hand, allowing the Constitution to become a flexible document opens it up to serious corruption by whoever is in power – unless rules are written in stone about how often it can be modified and to what extent.
So yes, I believe the Constitution should be malleable – but not in its entirety. The most basic clauses should be set in stone and unchangeable through the ages. Amendments such as the second should be considered corollary, and subject to scrutinization based on current times.
The next question would be, “How do you determine what is set in stone and what is corollary?” Anything that can be considered a basic “Human” right, or anything directly related to creating a fair existence should be set in stone. Anything that is dependent on external affairs [i.e. a war necessitating a militia] should be considered a corollary.
This is just a rough draft of my thoughts…