Not necessarily, maybe you just don't feel like being in a dungeon at that moment. The thing about XIII is that almost the entire game is one big linear dungeon, every moment is pure torture, the opposite of fun, AND there is absolutely no escape for the vast majority of the game. No escape, no choice of what you want to do. I just don't see how someone could reasonably say that XIII is not more linear than the other FF's. It just is!
なんだかずっと夢を見ていたようだ
The lack of choice i would definitley consider a flaw, whether it was intended or not.
FFXII CAN have a greater pace if the player chooses to push the plot forward or you have the choice to do something different. FFXII gives control over players AI but also the choice not to use it. FFXII offers multi-paths. You can choose to take a left or a right, whether that be simply an alternetive route through one area or by passing a different area entirely.
The problem with FFXIII is you're being told where to go, how you progress on the crystarium, what to do and even how to fight. There is nothing but to play the way you're being told. I wonder why the game even needs me at all, why not cut the crap and just move my character forward to the next cutscene for me. The formula of walk-fight-cutscene gets extremely tedious very quickly. If you're incredabley impressed with the plot and enjoy the battle system then you can make it through the entire game fine, but how many people have you heard giving up because they're bored of it?