I'd love to see more realistic NPCs. Instead of NPCs that do the same routine and don't say anything until you target them and hit Enter or X, that look more like just parts of the scenery than actual people, I'd love to see NPCs talk from noticing me passing by them. Perhaps an invitation to come check out what they have at their shop. Perhaps an announcement from a city official, like Age of Conan had in Tortage City. I'd love to be able to run through an area and hear real conversations between NPCs, and maybe having them actually look at me and wave or something, all with their own actual voices instead of just text. Perhaps a taru could have a cute little taru voice running around and all you hear is "Oh where it could be? Where could it be? Damnitaru!" and you target and engage them and get actual animations and voice acting and find out about the poor Taru's missing scroll. The NPCs could be given a large variety of things to say so it's not even the same thing each time you pass through.
FFXI NPCs were too frigid. Too stiff and lifeless. Without PS2 limitations, I know it can be done, as Oblivion ran on the PS3 easily with this form of AI.
What do you guys think?