One of the main difficulties for me in trying to find post-crisis Superman stories that were pre-crisis in spirit is that a good percentage of the post-crisis run was really part of a much larger continuing story arc. There were very few actual stand-alone issues. I suppose that in theory there could have been a long story arc that was pre-crisis in spirit, but to me having an extremely long story with chapters by different writers and artists which plays out over the course of a year is a very post-crisis specific concept that would by its nature preclude a story from consideration.
So I would only nominate a story that was for the most part self-contained in one issue, maybe two issues max if it was really good.
Further, I only read about half of the post-crisis Superman comics, because I would continually drop the Superman titles in frustration, then pick them up again, then drop them, then pick them up, then maybe just follow one or two of the four for a while (trying to follow creators I liked and avoid ones I disliked, a difficult thing to attempt in the triangle era), etc; continually repeating that process over the course of fifteen-or-so years.
The story has Superman be both intelligent and humanitarian. When Vartox, who, as usual favors flying all half-cocked, Superman instead refuses to just apply force to the problem and creates a plan. He reins in the instinct to kill and insists the others show mercy. In other words Superman behaves as he ought to.
True, Julian - but I don't think that a pre-crisis Superman would have to "reign in the instinct to kill." That's a definite Jurgens touch.