Who doesn't want a bigger party? Granted, this does break a few things on the balance and replayability fronts, as the game is meant to be played with four characters and then replayed later with four different characters, taking differing options along the way.
But who wants to play the game the way it was intended? If you want all the pre-built origin characters together in one playthrough, now you can go wild with a full group of six party members. It's a good bet those devastating boss battles won't be nearly as frustrating anymore either!