I feel not just Ash was lacking, but when you really think about it, the areas of the game are each about the size of two FF12 areas. The thing is, FF12 had like 20 of them, not four. Sure, you have some dungeons you don't return to in FF16, but you had them as well in FF12.
And when everyone is just jumping around in sidequests despite these locations being supposedly hundreds of miles apart, like late Game of Thrones seasons, you just lose all sense of scale.