Really there's no comparison to "Illmatic". The album as a classic in that era. An album that every rapper had. One of the first album to get 5 mics. Only one I can think that can compare is "Ready to Die". As far as superior I really don't see any album that's superior to it. But equal to it maybe.
Illmatic is my favorite and I feel the best hip hop album of all time but people need to stop praising it like its so far and away the best album and nothing comes close. A lot of albums like Reasonable Doubt, The Low End Theory, Liquid Swords, 36 Chambers, Resurrection, Blackstar, ATLiens, Paid...