THE only thing that can make FFXIII better is: (no spoilers)

[Zargabaath]

I just wish that like in FFX that they made all of the FMVs and music available to listen to. But I think FFX is the only game that did that. Which is really disappointing, because it was a really nice feature in the game.

I loved that feature as well in FFX and would like to see it again but it wouldn't make sense in any FF game outside of Spira since the music (somehow) and the FMV were captured in the "memory spheres" (?, whatever they were called). Now they could have had a feature in FFXII and FFXIII where once the player beats the game there is a "theater" - to view all cutscenes and FMV, like in Shadow Hearts: Covenant, and to listen to the music. Or they could have had the feature from the beginning and once the player experienced a cutscene or music it would be unlocked in the "theater".