I just think things can get a little too vast, a little too over the top. AC wasn't very visually attractive to me, the "overworld" I mean, but its smaller areas were okay if not convoluted. AA on the other hand impressed me because while it had plenty of space, it was one large and connected environment that made it feel Metroid-ish. Dark Souls did the same kind of thing and it was phenomenal.
I'm just saying that while the concept of big overworlds sounds good on paper, I've rarely actually had fun with it. The Infamous games are a big offender when it comes to this. I realize I may be in some minority, but I do not enjoy traversing gigantic overworlds with samey visuals. Large interconnected environments as found in Arkham Asylum and Dark Souls are vastly more entertaining, fun to explore, and impressive to me. I like good, focused level design over anything. I don't care how big the world is if I'm not having fun, or if I don't feel like I'm having a tight gameplay experience.
I don't know how many times while playing Dark Souls, where I said "holy shit that brought me all the way back here?" But then when I thought about it geographically, it made sense and really blew my mind.