This brings up the question of what would happen if we passed an amendment repealing the commerce clause.
Specifically, would existent laws deriving their ‘justification’ from that clause be null and void automatically; or would each law have to be challenged individually (also giving the government the time/ability to justify that law via some other route)?
Probably not nullify related existing laws but would deny future similar perversions of the "commerce" clause.
It's useful to note that corrupt Justice Deparments have not been successful using any other existing clause in the Constitution to abuse citizens with a similar, creative, swiss army knife interpretation similar to "interstate commerce."
The proper approach would be to have statutes recognize that in cases where the application or applicability of a law could be dependent upon contested factual matters, the defendant has the right to have a jury make the necessary factual determinations. With regard to the Commerce Clause, it should be necessary for the prosecution, when prosecuting "Commerce-clause" statutes, to demonstrate that the defendant's conduct materially interfered with a legitimate exercise of the Commerce Power. The fact that 99% of the people who violate a statute do so in a way which the federal government would have the authority to forbid, should not preclude the remaining 1% from prevailing if the federal government could not demonstrate that their particular actions would not interfere with the federal government's efforts to regulate interstate commerce unless the federal government went out of its way to ensure that they did.
This principle should apply in many other cases as well. For example, to rein in the outrageous conduct of some police conducting "searches", the states should recognize defendants' right to have juries evaluate whether searches are in fact conducted in "reasonable fashion", and whether warrants are based upon "good faith" probable cause. Juries should be instructed that if they do not find credible the justifications for a warrant, nor the claims that a search was performed in "reasonable" fashion, they should not construe any evidence gained thereby in a manner detrimental to the defendant.
To be sure, judges should have a role in keeping from juries evidence that the prosecution obtained via clearly-illegitimate means, since juries might not always disregard things that they should. On the other hand, the fact that a judge finds that something wasn't patently unreasonable doesn't mean that it was, in fact, reasonable. If "trial by jury" includes the rights to have jurors make a veto-proof determination that prosecutor's witness is not credible, then it should also include the right to have them make such a determination that prosecutors' claims that warrants were issued in "good faith" are not credible, since such claims will invariably depend upon witnesses.