That's a really good question! Took me a while to figure out which jobs it should get, because most of the existing jobs in Bravely Default are some-what similar to most of the FF Jobs, which are already in games.
How about Beast-Tamer? I know the Vampire class is kinda like the Beast-Tamer, except with the Beast-Tamer Job, you can actually like "summon" the beast in battle (kinda like Summoner), but can only use it once, I don't know, some exceptions should be applied, but I think that'll be an interesting job.
I think a Puppet Master class would be epic as well. Remember Lulu from Final Fantasy X, something like that except the puppets actually do (a lot) of damage, and can use different abilities, etc.
Also, Dancer? Except not really a fighter, but can do buffs on the team, and cause status effects?
This list could be endless, I do have a lot of faith in Bravely Second though, I have a feeling it would be much better than Bravely Default, so I'm looking forward to it, and I'm sure I'd be pleased with whatever they brew up!