This is hardly arguable, but personally, after some time playing I begin to recognize animation/sound/timing (i.e. behavioral) patterns of non-plot entities and that ruins the entire experience. That's what retains me on the storyline and prevents free exploration -- there is nothing really interesting besides nice graphics. I think there is a room to evolve from [hundreds of] programmed random encounters to purely independent world.
Actually, I'm fine with GTA3/GTASA-like graphics, like I was with roguelikes and physical book-and-dice quests, so idk how that applies to wide public.
ps. Another conclusion, it may appear too frustrating. We probably play games to win and achieve. If there is no end, no goal and no perfect winning strategy, that understanding alone may cause depression, like IRL.