Let's go back to my hypothetical posted earlier.
Back in 1800, the states would not have needed Congress to call for a single-subject CoS; they would simply have instructed their Senators to introduce a bill in Congress to propose the amendment. The other states would then have supported the bill or not.
Your "common sense" aggregation of single-subject amendments is really the other half of Article V's amendment process; single-subject amendments introduced by Congress.
The fact that today's post-17th amendment Congress has gone rogue doesn't change the original intent of the proposing convention: proposing amendments, not an amendment.
-PJ
Ah! But there's the "rub": The original constitutional "architecture" that recognized such powers of the Senate was utterly destroyed by the Seventeenth Amendment. THAT order is completely gone, owing to a frenzy of populist reaction to the public corruption of the times.
These "progressive" populists evidently thought that a one-man-one-vote per citizen regime on any and all public questions was superior to the Constitution's plan, which called for institutions designed to mediate the effects of transitory public faction and frenzy. Such as the Senate — designed not to represent the people directly, but the several States, the ratifying parties of the Constitution.
The Seventeenth Amendment took a wrecking ball to the very foundation of the Constitutional vertical separation of powers as between the national government and the several sovereign States, by denying the States representation in Congress.
I think the Seventeenth is due for repeal. We have all seen its pernicious effects....