I think what makes the game enjoyable is the fact that no two times through are going to be 100 percent alike. What I mean by this is how your party members level and what brave/faith they have and where you spend your time using them.
of course the main game will stay the same, Algus will always be a douchbag, and your maps might get boring. But hey, when you now have an awsome mage your second time through with 24+ magic and fire dose 300+ damage, its fun.

By the way, the official soundtrack owns.