JC isn't going to get any flack from me about "property requirement" for voting. Most of the former colonies not only reinstated it after the revolution, but increased the limit from L50 to L100 .
How ever, that was the primary cause of Shay's rebellion in Mass, so do not consider it unless you are prepared to machine gun the lower classes to enforce it.
Along with changing the Senate from appointed to elected another thing I have thought about is the Women's vote. I haven't come to any definite opinion but I notice that before women were allowed to vote debates were focused insights, and idea's based on thought, look at the debates on slavery, or the gold/ silver standard. We also elected men who while physically unattractive were thoughtful and intelligent.
Since then we have had a series of "handsome" nonentities except for FDR, who was supposed to be an extremely charming guy. And our debates have become less focused on the reality of facts and more geared toward, emotion and what's "fair".
The Constitution was never intended to be "fair" it was intended to be workable while screwing the smallest number of people.
One thing I agree with the liberals about, we need to toss the old Constitution and rewrite it to remove all wiggle room. For 3 things, it needs to include specific penalties for violations by politicians instead of the current ethics process which is a joke, you have people like Charlie Rangel who have spent more tome in there than some of the members with no consequences, corrupt politicians should be either executed immediately, or immediately removed and forbidden from ever holding any position of trust, no professorships, no board of directorships, not even dog catcher.
Secondly, some one needs to be specified as being responsible for enforcing the Constitution and given the muscle, and independence to make it stick, I don't know how you would change the selection process to make it work, but the general idea would be that all laws and policies are reviewed by SCOTUS before being implemented, and if a President or Congress tried to defy them give them the authority to use the Army to remove the offenders.
Third, No more Bill of Rights, instead, put in place a "Bill of responsibilities", for example, you must be able to support what you say and print with verifiable facts, (that would eliminate global warming, gun control, and most other liberal BS) the obligation of the citizens to keep and bear arms, and so on.