Disagree on collision; while it may provide "immersion", it's frustrating on many other levels. No collision with NPCs PCs, and monsters is huge for convenience.

Agreed on monster behavior, but the problem with that is that EVERY monster before acted the same anyways. They all had a ranged attack, they all aggroed the same, they all had the same chase distance, and there were way too many that just sat there and followed you around (compare that with FFXI where only one or two types did that; there, it was a more unique behavior). There was zero creativity put into the monsters from the start.