I love the final battle and how it ends - so including the ending of Final Fantasy XIII as well.

You think the sidequests are riddiculus, so easy. But that depends on how you fight your enemies and on your equipment. With the (SPOILER)Genji Glove and the "Highwind" technique of Fang you can easily deal 3 million damage points. Missions like 62 or 63 can be very hard if you just start the battle without any preparations. And of course for the "L'Cie Paragon" it is even harder to do some missions because you have to beat your mission monster with rank 5.