Great thread.
I went with IWW. I think in a head to head comparison, it's the superior album.
That being said, I can see a case for ATLiens as the superior "sophomore album".
Both albums broadened and existing fanbase, but Kast did it organically while Nas went to the Trackmasters to get that commercial love.
Dre and Big Boi both ramped up tremendously on the mic, but still trailed IWW Nas. So that's sort of a push, yeah Nas didn't improve on the mic on IWW, but he didn't need to, shy of :pdahell:he was the best rapper in the game at that point.
Dre and Big Boi started producing on this album as well.

Nas started singing hooks from pop songs :tochilol: