It's time for Final Fantasy to change the formula.
Where XIII takes a turn for the worse is the level design and the story itself. I'm not sure if the idea of not giving the player very much information as to what's going on in the story but it's not something that wants me to play the game more to figure out if they ever fill me in.
In my opinion, this is the worst experience since playing FFVIII. I felt like I was still in tutorial mode 7 hours in.
The level design is what you've heard - narrow. The huge worlds and they're basically just a painted landscape. It's as if you have to run a gauntlet to a clearing so you can wait for a cutscene in hopes that you can find out a little more of what's going on.