I think IWW will help you love Illmatic over time if you didn't already. I first heard all of IWW before I heard all of Illmatic. Remember it took to from 1996 to 2001 for Illmatic to go Platinum. And Nas had a MTV buzzworthy video along with Nirvanas "Smells Like Teen Spirit" Thank West Coast Dominance , "Snoop Dre,Warren G,Cube etc." and no strong radio single for Illmatic poor sales.Hits sell albums.
If you don't have a ear for traditional sample and kick drum based Hip Hop then you wont absorb Illmatic all the way at first.
IWW has beats that a 16 year old or 36 year old will love still if you played it now.
Lyrically Illmatic has more poignant life observations especially as you mature. "Buck that bought a bottle..." *Life's A bytch" "the intro", " "through out the walls of intelligence life is defined" writing his friend in Jail on "One Love"etc.
IWW has the flyest bars tho.
IWW has a straight forward theme but also mystique to it. Lyrically You got mafioso, mixed with pro-black 5%er influence, QB slang, mixed with commercial r&b and homages to the old school rappers with samples from Kool Keith Ultramagnetic on " Take it in Blood" and Kurtis Blow "If I Ruled The Wirld
Also the strings on IWW are well done like Affirmative Action" and the right mix of grime and polish production-wise.
Sometimes I think IWW gets snubbed because it doesn't have an overt "concious message" like alot of Illmatic does.