The first NWA song I ever heard was "A Bitch Iz a Bitchh," which was, quite frankly, offensive ("Now, the title bitch don't apply to all women, but all women have a little bitch in 'em."), even if I had to agree with parts of it. So, as you can imagine, I was a little wary about having to analyze this album and consider it in the context of the literary.
As several people have pointed out, there seem to be repetitious themes throughout NWA's songs, such as murder, sex, drugs, and the rest of that good stuff. I haven't closely read the lyrics of even half the album yet, and I'm already a bit tired of this subject monotony.
There is one line in "Straight Outta Compton" that really struck me, though.
In the third verse:
"...straight outta Compton
Is a brother that'll smother yo' mother
And make yo' sister think I love her"
I think it's interesting that Eazy-E compares murdering someone's mother and breaking the heart of someone's sister as if the actions are equally as grave. I sort of have to respect a person who believes that romantically deceiving a naive girl is equal to killing someone. It shows a personal honor code (the Wire!) that, while deviating from the conventional, has no tolerance for deceit and betrayal. While NWA may be involved in drugs and murder, they have a high regard for loyalty and to some extent others' emotions, which is an aspect that I think could easily slip by most listeners.