“Repealing” that part of Article V would be the equivalent of getting rid of the Constitution altogether. Sure, the People could gather together and adopt a new constitution with a new form of government, but that’s basically a new American Revolution. Under the constitutional framework that we’ve had for 225 years, what Sabato implies is a non-starter.
BTW, Article V does not prevent the number of senators per state to be increased, just that no amendment may deny a state equal representation in the senate without its consent. I think that we should amend the Constitution to increase the number of senators to 3 per state, and to set the number of Representatives at 3 times the total number of senators. That would allow the citizens of each state to elect a senator at every biennial election. It also would result in a ratio of representatives-to-senators of 3:1, which is much closer to the 2.5:1 ratio for the First Congress than the 4.35:1 ratio that we’ve had for the past 50+ years.
This ratio matters because a higher ratio benefits larger states in the Electoral College, thus watering down the federalist principles behind the Electoral College. A small state (population-wise) like SD currently has 3 electoral votes out of the 538 total (0.5576%), but if the Senate had 150 members and the House had 450 SD would have 4 EVs out of 604 (DC would go up to 4 EVs as per the 23rd Amendment, although you already know what I would do with DC), which is 0.6622% of the total. This increase seems small, but such amendment would serve as a prophylactic measure against the possibility of Congress increasing House membership to, say, 1,000 members, which would markedly reduce the importance of small states in the Electoral College.
Another benefit of linking the number of representatives to senators is that current states no longer would have a selfish reason to deny a new state being admitted, as currently is the case today where the House by law is set at 435 members even if new states come in (House membership is increased temporarily when new states are admitted, but goes back down to 435 after the following Census). When Congress was debating a political-status referendum for Puerto Rico in 1998, entire House delegations (including IL and TN IIRC) voted against the bill because the Congressional Research Service pointed out that, if PR became a state, such states would lose a representative after the next Census. Admission of a new state should be made on the merits, not based on how many representatives current states would have. With the rep-to-senator ratio set at 3:1, only if a proposed new state would be entitled to more than 9 representatives would its admission harm existing state delegations, and it’s unlikely that new states would be considered that would exceed this number of representatives by too much (although if California was split 5 ways and L.A. County was its own state it would have like 13 or 14 representatives; I would hope that Republican or marginal areas in L.A. County would secede prior to CA splitting, which would reduce the size of L.A. County so that it would have closer to 10 representatives).
So that’s what I would do with Senate membership. Larry Sabato can put that in his toupee and smoke it.
I've long thought that is a good idea, if only because that would be nice and even (or odd if we added another state, even better). Also that the House could stand to be a little bigger. Most freepers balk at the idea because if Congress=bad then bigger Congress=worse, a simplistic way of looking at it.