Investing in a Thief seems good (Mia is fine if you play safe with her). Steal can get job memories which might be much better than the drop rate.
Farming Elemental Awakening mats from the Alcrystals stages is long and boring (the first two stages aren’t bad since there are chests, but level 3 and beyond have no chests and you’ll likely get like just 1-2 drops per run). It’s not so bad if you’re afking auto on multi but it still seems like one of the most pointless grinds in this game.
I wish gacha would have higher difficulty rates for higher drops on all stages. One thing I appreciate about Star Ocean Anamnesis (especially Episode 2 which had the same for story missions).