Originally Posted by
Cleretic
It's been an EXTREMELY long time since I've played the Thaumaturge questline, but I believe it's ambiguous whether Cocobusi has no aether manipulation capabilities or just extremely reduced, just that it's enough to knock thaumaturgy off the table anyway. If it's the former, every single magic job is completely unviable just on a base level; it's just not possible, end of story. If it's the latter... I actually think they're still all off the table, because the main reason Red Mage is aetherically economical is because it uses internal aether rather than external... but internal aether is the central problem for Cocobusi anyway. If it's so bad he can't even use an externally-based magic style like thaumaturgy, he can't use ANY of them. He can't just be a 'part-time' Red Mage or something, that'd be like suggesting that Arenvald become a 'part-time' walker.
If we instead turn to the Disciple of War jobs, we've got the ones that have already been mentioned: Machinist, Gunbreaker, Ninja, and Reaper are all either invented for people who can't manipulate aether, or are used to a pretty decent level by someone who can't.