It's pretty much said in the epilogue:
andThere were still so many places that they hadn’t seen yet, hadn’t traveled to. If she searched there, she might find what she was looking for. The only thing was, it was dangerous now that she was no longer l’Cie. Gran Pulse was filled with monsters of all kinds, handling them would be no small thing. It would be a long trip.
Neither would Hope. While he had been strong as a l’Cie being able to summon Alexander, now he was a normal boy.
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