Ah. That's a fair point. I thought perhaps you were just jabbing at the supposed "gun nuts" who own multiple guns. Obviously, there will be restrictions on the types of arms that are allowed. But the jump to cruise missiles, etc, is silly, as it's clearly referring to personal arms.
The "musket" argument really isn't valid, as "arms" was used to be future-proof. If it was meant to be restricted to musket-type arms, it would say that. I don't think it needs to be rewritten, but it does need SCOTUS clarification to cover the fringe people on both sides (those who think they've the "right" to own a gatlin gun, etc, and those that think arms in general are "bad"). The problem mostly lies in misinterpretation. On one side, you have those who, like you've said, think "arms" covers everything, which it doesn't. On the other side, you have those that like to point out "well-regulated", which actually refers to self-regulation (ie, law-abiding citizens), and "militia", which refers to individuals who are capable of defending themselves, their land or even their country but aren't part of the military, rather some "citizen army", etc.