They could take another page from FF6 with how they have magicite as well as relics that are either for all characters/jobs or just specific ones.

Like for example the dragoon boots relic in FF6 changed the characters attack command to jump, they could do a similar thing here but adapted for XIV's mechanics. Maybe the double jump thing, and have it be a thing only dragoon can use.

Or for something more tangible, take the magicite mechanic and turn it into equippable gems for summoner that change its summons into bismarck/leviathan/shiva/etc etc other summons

I think both of those to be honest would be a neat feature to include as the new exploratory zone's logos/lost actions mechanic (assuming it has one)