Nas is, in my opinion, the best lyricist of all time. Being a Lupe fan also, you'd love nas because they're both great lyricists. Ice Cube made it ok to talk about what goes down on the streets and had such a strong message.
Tupac had such a strong message and even though he isn't the greatest lyricist, he has some of the best hiphop songs of all time. Don't really listen to GZA so couldn't help you on that one.
I'm surprised nobody's mentioned Jay. If you asked around you'd probably hear someone mention either Nas, Jay-z, Biggie, or Pac as the G.O.A.T. Lupe is actually very, very talented. I'm a fan of his too.
But you need to check out some of the albums by the rappers I just mentioned.. Try... Jay-Z: The Blueprint, Reasonable Doubt Nas: Illmatic, It Was Written 2pac: Me Against the World, All Eyez On Me Big: Ready To Die, Life After Death.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.