Hey everyone, i just got beat Bravely Default and I'm prepared to give a PSA to you guys. The last few chapters before the Endgame are frustrating (that's a nice term for it). You'll be undergoing a repetitive task that gets really boring really quick. BUT that's OK because that's why I'm here to warn you about it without spoilers. :)
Chapter 5 starts the nonsense which will be the bane of enjoyment you have. But once you reach Ch 6, I definitely recommend you turn the difficulty to easy (or use a cheating ninja squad) to breeze through the tediousness which ends after chapter 8. There's only a single sidequest that rewards a job on ch6, all the rest are for backstory (backstory is worthless at this point imo), assuming you got the Vampire class. So, yeah, there's little story progression in chapters 6-8 anyways so, like I said switch your difficulty to easy and get that story rolling. Then if you're under leveled when you're at the endgame, just hunt down genomes or grind in the Earth Temple.
The reason I say this, is because the true ending of Bravely Default was completely worth switching to easy mode for a few chapters.