This is the problem with everyone picking Cleric Stance in the healer role. You get screamed at, shouted down, and basically told you're a bad player if you don't have it, because maybe you wanted something else with more utility. If you don't follow the BiS guide for best rotation from some arbitrary wiki, good gawd you're a bad player, don't even play this game /s.
Yet the only cross-class skill that has ever felt necessary on healers is Swiftcast (and even then, just to avoid cast times of StoneSkin II and Revive.) That remains in the role system. Ruin, Psysick, Virus, Blizzard II, all gone. As Conjurer, you also lose Convalescence, Provoke, Awareness, Featherfoot, Second Wind, Internal Release, Mantra, Foresight Bloodbath, Mercy Stroke, Keen Flurry, Invigorate, Blood for Blood, Raging Strikes, Hawk's Eye, and Quelling Strikes already when you switch to White Mage. This is why the class -> Job system is broken.
If you're playing SCH, you still keep the arcanist skillset. But can pull Cure, Aero, Protect, Raise and Stoneskin from Conjurer. Yet because Arcanist is a DPS and Scholar is a healer, you don't get to pull any of the other DPS job skills you do as Summoner. Yet why would you want to pull Cure and Raise from Conjurer when you already have Psysick and Resurrection from Arcanist? Why does Arcanist have these skills if they are a DPS?
See how this is a mess?
Class = Access to all the cross-class actions (most ending at level 34, and no passives), Nothing from Astrologian, Dark Knight or Machinist can be cross-classed, because they don't have a class.
Job = Access to only cross-class actions of Two Melee or two Caster types related to the class
In other games that have had cross-class systems, every class had some kind of wanted skill in the upper levels of that class that made leveling that class useful. So your character would have all the BiS skills from every class. That is going away.
What should be expected when the "class" system disappears at some point is that the arcanist storyline get's moved to Scholar, and they create a new storyline for Summoner to replaced the arcanist storyline. The storyline itself fits more with the Scholar theme. Then just to be fair to everyone Square-Enix will let everyone reset the Level 1-30 storyline on any class, and the most obvious change will be the replacement of the former class name with the job the entire time, and the "job stone" aspects just disappear entirely.