I think it's....

...the setting. The world setting feels a lot more Western and a little bit more techy than the Final Fantasies I'm used to. The addition of Chocobos, Airships, and hopefully some more familiar monsters from the series will go a long way. The story is also a little different as most of the time it's Band of Heroes vs. Overlords, but right now it's more like "Everyone vs. Garleans, but doom is going to come from somewhere else this time." There isn't much conflict between you and the Garleans right now (SPOILER) Until later on in the storyline.

The music is fine I think; besides the idle music, most of it is pretty much remixes of several musical scores from past Final Fantasies. People hate Gridania because the outside is a latticework of trees and paths and the inside is completely spread out so that it's a total pain to walk anywhere worth going.