In the spirit of the question asked, it has to be Augusta National.
I've been there; I know its nuanced details; it's history is modern golf's history, launched by the great golfer of the pre-modern era. Take away Augusta National and what golf is changes for me; might not be as precious, mythic or singular in the imagination.
No slight on Cypress Point, but remove it and there are other plum venues with singular courses; history and the ethos don't change too much for me.
Though that is enough for my choice, I also think that to some extent, God (or the like) gets a co-design credit for the impressiveness of Cypress, while by comparison, Augusta National is entirely a conjured idea made by the mind of man... and I kind of like that better in the design realm.
...If I gave an honest "what I want" answer I would not play either, I'd play a course I've played, that I've enjoyed, where I have memories and really brings out my best game...among the good ones that fit that bill, it would be Yale or Fishers or CC of Fairfield.
cheers vk