I would personally have no objection to making naturalized citizens eligible for president by an amendment. Perhaps after 20 years or so.
Not that I think naturalized citizens are better, but simply because so many indisputable NBCs are so fervently anti-American.
The notion that an NBC will be definition be more loyal is quite simply false on its face. While the NBC requirement remains in the Constitution, it should be followed, but to my mind there is no logical reason to retain it.
Personally, I think there's issues that have a much more pressing need to be amended than presidential requirements, even with as much distaste as I have for the use of what is now essentially undefined. See here.