I would actually say it is lyrics AND beats AND song concept/structure (people like Canibus really lacked in this last category)
I thought Vol. 1 had pretty good production.
Million and One/Rhyme No More, Streets is Watching, Friend or Foe 98, Where I'm From, Rap Game/Crack Game were all raw as hell. Who You Wit II was a banger. The beats for You Must Love Me, Lucky Me, Imaginary Player, Face Off, Real Niccaz were very solid and fits the songs well.
People hate on Sunshine, I Know What Girls Like and City is Mine. Personally, I loved everything about Sunshine (beats/lyrics/chorus). I used to find I Know What Girls Like annoying, and I still don't love the chorus, but the beat is solid and Jay flows on it well. City is Mine is an okay song. Not great, kind of weak chorus, but I appreciated the concept and sentiment.