Nas spits about EVERYTHING. The fact he tries different shyt on every album is exactly why he has the best catalog of all time.
Whats the big difference between I Am, Stillmatic, Nastradamus, Hiphop is dead and God's Son. Lyrically It's dreaming, being poor, being rich, surviving and over coming and relationships. Those are wide topics.
And he talks about those topics a lot of times, in different ways LYRICALLY, but he keeps the same flow, delivery, rhyme schemes, sounds of production on a lot of albums and songs. The overall mood setting of the albums are also very similar. Which is why he doesn't have the best catalog in my opinion. Tyler the creator talks about different shyt too, but the shyt still sounds the same.
You could move around a lot of Nas's songs on to different Nas albums and they would fit on there like nothing, cause ain't much changed. I appreciate that he holds the same quality but a little more creativity, courage to do (not say) different shyt, move outside of your comfort zone like Untitled which slightly was outside of his comfort zone just slightly. It's been 18 years since he came in his game and he's still keeping it very similar to how it was when it came out just weaker and weaker production. That's why as a poet Nas is probably #1, just of reading his lyrics. But when I listen to the music he moved down a few spots.
That's the only negative thing I can say about Nas, just like I can say 1 negative thing about all the top 10 rappers besides maybe Pac and Big cause they had such short careers.