"Seasons in the Abyss" has many great songs also. "War Ensemble," "Expendable Youth," "Dead Skin Mask," and the eponymous track are all amazing. The fact that it compiled some of my absolute favorite extreme metal songs into one album made this my undisputed favorite.
I thought that "Eyes of the Insane" off "Christ Illusion" was a pretty good track, though I never really checked out the album as a whole.
Your Slayer collection is much greater than mine (which currently stands at absolute zero), and actually outnumbers the total number of thrash albums that I actually own (2 - I am no great fan of thrash either). I really need to get some new music.