I miss them for the sole fact that it made the game dangerous, it made your pulse race, it made your head pop up from the already going-bad battle and quickly look around accessing your chances of survival.
I fondly remember tensing up in Mistmoore after hearing TRAIN, trying to spot where the danger will approach. I'd run for a safe spot, hoping it would not respawn while I watched the train walk back to their places. We'd track them and report to the zone how many have passed and when it was safe to resume. Sure you could get train-ed by some tool, but that was part of living and dying in EQ1.
EQ2 has been homoginized and tamed to the point of anyone can run through a zone with relative impunity. A group of passing orcs can see that guy but not me? And don't get me started on close-to-nil death penalty and effects.
It has totally changed the way players approach the game and has produced an entire generation of what I'll call, Careless Players. Since there is little-to-no danger or penalty, there is no reason to play smart and cautious.