All of your "objections" refer to this basic circular argument - you say that because Obama was certified as qualified, then he is qualified. In other words, your position is that any challenge to his qualification must take place upon the presumption that the qualification was valid, because - it took place.
But my disagreement is based on the long accepted legal effects of fraud, which is that it vitiates all process. Which means that if the certification of qualification was fraudulent, then the certification was fraudulent, and if the certification was fraudulent then the qualification never legally took place at all.
And while perhaps presumption of legality could force an initial presumption of qualification, and thereby require a tortuous legal process to get "standing" for a challenge requiring legal review (i.e. the whole birth certificate mess), such presumption of legitimacy would not be justified in the case of prima facie evidence of fraud.
And what is the admitted non-American citizenship of Obama's father but prima facie evidence of the impossibility of his having natural-born citizenship?
So given that, I can't see how the certification of his qualification under 3rd/20th could be seen as ever being legitimate, since it is openly, obviously impossible. Thus, the certification of his qualification was falsely affirmed, thus qualification never legally happened.
Given all of this, if you still believe presumption should be given to legitimate qualification, there isn't much else I can say, except that I don't see your escape from the vitiating effects of prima facie fraud - and that it would be nice to see this issue addressed by SCOTUS.
Because in the context of that specific amendment, that is what they meant by "qualified". That amendment was written specifically to address contested elections and problems with the Electoral College, and of course the death of a president-elect. None of those things occurred with Obama - in other words he qualified well before the date of inauguration.
A plain reading of the text clearly reveals that the purpose of the Amendment wasn't to provide an additional vetting step before the the inauguration, but was to address exceptional circumstances - like the ones I've mentioned, and the ones the Amendment specifically addresses. It's as simple as that.
"And what is the admitted non-American citizenship of Obama's father but prima facie evidence of the impossibility of his having natural-born citizenship?"
This issue was raised prior to Inauguration. The Supreme Court didn't find the argument compelling, which is why they denied cert twice, both times without comment.
If fraud was committed by the POTUS while in office, or committed by POTUS to obtain his office, then that is a matter for Congress to investigate and prosecute if so merited. To date, that hasn't happened.
But, it isn't for the Judiciary to decide this issue, for it would violate a number principles in American jurisprudence to include standing, justiciability, the Political Question doctrine and the separation of powers.