At a threshhold LOWER than that of amending the Constitution.
How about we instead work on getting the 10th elevated back to its proper place? We already have checks and balances on federal power - that are ignored - the solution IMO is not to create another check that will be ignored, but to get the existing checks and balances restored.
Certainly lower. Repealing legislation and obnoxious regulations ought not be as burdensome as amending the Constitution. If we had Senators who were appointed by the governors and legislatures of their respective States, perhaps they would be more effective at representing the interests of the States, and not just serve as some sort of super-representative. Then this sort of nonsense would be unimagined. And yes, I agree with you about the Tenth. The problem is that we have created all this as a result of 100 years of unchecked progressivism. These misled cretins have been disassembling the Constitution since long before I was born and I'm nearing 70. Unwinding their damage would be ideal, but I fear the best we will be able to do is to repair it as best we can now and go for the cleaner fix when it finally becomes possible to do so.