I'm not disagreeing with your general premise that the fundamental right for equality is the basis of the constitution and therefore equal marriage is implied by it. But to your points:

"the right of black people to be free and equal to the other people" (specifically the abolishment of slavery) Is made explicit in the 13th amendment[0]

And "women's suffrage" is the 19th amendment[1]

So for both of your examples, these things are explicity added to the constitution.

[0] https://en.wikipedia.org/wiki/Thirteenth_Amendment_to_the_Un...

[1] https://en.wikipedia.org/wiki/Nineteenth_Amendment_to_the_Un...