No, the authors of the Constitution designed a society specifically set up to place wealthy, white, male landowners in exclusive control of society. Slavery was built into the system from the start.
No, they designed a distributed government of limited powers. History and documents and letters from the founders show that the founders wanted to eliminate slavery when the Constitution was written, but they would have lost the southern states and consequently the revolutionary war against the British if they did not ignore the issue at that time.
"Great as the evil of slavery is, a dismemberment of the union would be worse." - James Madison
"There is not a man living who wishes more sincerely than I do to see a plan adopted for the abolition of slavery." - George Washington
"Every measure of prudence therefore ought to be assumed for the eventual total extirpation of slavery from the United States. I have, throughout my whole life, held that the practice of slavery is an abhorrence." - John Adams
There are many more.
As to the "3/5ths" issue, it was only for purposes of the census that slaves were counted as 3/5ths of a person so that the slave-owning states did not acquire an unfair advantage in the number of their representatives in Congress and block any effort to end slavery.
Slavery in the American colonies was started by a black man, Anthony Johnson, who owned a tobacco farm, not a white man. Anthony Johnson, a black, fought in the courts to become the first slave owner in the US. The first black US Senator was Hiram Revels in 1870. The army was non-segregated up until President Woodrow Wilson (D) segregated it.
Concepts like ordinary citizens being able to vote for their national legislators were specifically circumvented.
Voting was at first limited to land owners as a practical matter, as they were the only ones likely to be educated enough to be literate and comprehend what they voted upon, and would be the ones paying the taxes to fund the results. This changed after literacy rates improved.
If you meant the time prior to the 17th Amendment changing US Senate seats from State legislature-elected positions to citizen-elected positions, I believe that was wrong and that Amendment should be changed back to Senate seats being elected by State legislatures, as it has taken too much power away from the States and resulted in a nearly omnipotent Federal government.
Yes, the Constitution contained some good ideas; it's not pure evil, and parts are salvageable. But, neither is it a blueprint for a free and equal society, though it has frequently been mythologized as such.
The US Constitution has resulted in the most free & equal society ever to exist as a nation. Nothing is ever perfect or can ever be perfect that is made by man. Don't allow perfect to be the enemy of good.
Go read some history from first sources, not someone else's interpretations. Read the Federalist and Anti-Federalist papers if you want to know what the founders intended regarding the Constitution in their own words. As you demonstrate with your reply, much of that history has been re-written or suppressed.