I know that the plan for Shadowbringers is to allow us to replay the previous storylines and I am personally all for that, honestly I will very likely do so quite alot..
But what about class/job quests? I'm not certain if it has been mentioned or not but honestly as much as the jump potions have been useful for my alts so I don't have to grind levels I've already gone through, and for soloing my way through most of the 2.0 storyline--- one thing that I've always hated is that it takes away getting to personally play through the storyline, which isn't all in the cutscenes (and with those you don't actually get them all either)
Even on my main characters there are times when I'd like to be able to replay the storylines just for fun, so I'm hoping that it's a part of future plans to make this a thing even if they don't reward you for doing the quests again the option to do so would be nice