Well, specifics are needed about what to update. When they wrote, all men are created equal, they were dealing with one revolutionary idea - the king and nobles were treated as quite superior to peasants, and they were radically recognizing at least white male property owners as more equal than they had been in monarchies. They were not thinking of and did not view slaves or women or "merciless Indian savages" as equal.
The "Great Emancipator" Lincoln said it clearly a century later when he said he opposed any idea of equality of races:
And yet, soon after, the US changed our constitution to, on paper, create just that equality under the law. No more slavery except for criminals, and no laws treating races unequally. Sure, culturally, great discrimination remained, but it was done under a pretense of "separate but equal" rather than 'officially' treating races unequally. It was progress.
A lot of what you criticize in the original document has been 'corrected'. Your point is now quite unclear. Are you criticizing the branches of government? The right to free speech? The freedom from unreasonable searches and seizures? The natural born or age requirements to be elected? Etc. I don't think the constitution is the problem. Plutocracy is. Including that plutocracy 're-writes' and destroys important parts of the constitution.