personal take on sage (and some light comparisons to it's scholar cousin)
For context: I've completed the story (round of applause for the devs, seriously) and haven't had the time to dive into EX trials just yet (busy week), giving my barebones impressions of sage having levelled it to 80 and then having played through the story dungeons/trials and EX dungeons on it, as well as doing daily roulette suites and extra runs to try and fish for minions.
gear is tomestone weapon and ring, AF left side, and EX dungeon right side so far.
[Overall]
It's rather as I predicted in earlier posts/threads, for good and ill: perfectly functional healer on the healing side (if a bit wimpy feeling) and sadly lacking a downtime activity like the other healers, so healing is overall still just unmitigated suffering to play, no matter how many -10% damage reductions you apply.
overall the gameplay is similar to scholar at it's core in that you largely use your GCDs for your damage spell of choice and your OGCDs+kardia to handle the reactive healing and general sustain, without as much of the patented (and now-reduced, anecdotally) "fairy jank" that we've come to know and barely tolerate (though 'stance delay' does add a familliar hitch to things to keep ex-scholars from feeling too out of the ordinary).
it also has the same sort of feast or famine aspect in that either things are well-handled and you are spamming dosis-clones or dyskrasia, or you are desperately floundering with the tank on 10% hp and you are completely dry on all resources (which can swiftly change from the former to the latter).
[The Good]
-looks great: the weapons, animations, particle effects, and sounds are all pretty awesome. loving the aesthetic.
-has some decent QoL: having an actual use for the shield layers being backwards (in that the crit shield is under the regular shield for some reason--an issue which plagues SCH's deployment tactics in particular) is nice, even if the toxikon you get is rather lackluster
-kardia is great: a more-efficient fairy, it's a helpful source of sustain for you or a target and makes aoe pulls much less of a pain. doesn't need to be placed on the field, doesnt have a tempermental timing, cant be outranged (other than outranging/LoSing you the healer), and targets exactly who you choose.
-eukrasia is good fun: honestly i wish there were more skills that worked with eukrasia, as only having the three feels like a wasted opportunity--though i understand their hesitance to make another dark arts.
-the scant healing-per-button makes a neat little game of "what spells/OGCDs do i ration out here for the tank to survive this pull without going into cooldown-debt and wiping the party on the next pull?", and has done a lot more to make me hyper-aware of exactly what my entire toolkit is and what is available at all times as compared to scholar's rather generous supply of solid healing and (now-buffed) shields. it has also forcibly broken me of my habit/preference of keeping everyone at or close to full HP while avoiding overheals, and now to a more generally reasonable 40-60% hp, since i've found it basically impossible to actually do the former as a sage without going into cooldown-debt and wiping the party.
sure, it's stressful at times, but it really leans into the sort of log horizon-esque power fantasy of skillfully managing your toolkit to squeak through situations you probably shouldn't have been able to (or rather, that a different healer could have done much more easily).
[The Bad]
-addersting (like the faerie guage) feels rather neglected: with having a rather niche situation to grant it, only a single skill that uses it, and the use of it being rather lackluster overall makes the entire mechanic feel like it was added as an afterthought. it feels like an anti-energy drain (SCH), almost.
-toxikon doesn't feel super great most of the time: it being tied to addersting/shieldbreaks puts you on the back foot in many situations, creating a dilemma of "do i apply another shield or use the toxikon i just earned, and will the tank die if i'm not using that time on another small heal or shield", and applying the shield just to get toxikon is simply a waste of time in most cases. it generally just feels like a more frustrating ruin 2.
-the actual healing feels kinda bad: I'd made a joke a while back that "i suppose healers wouldnt need downtime if their spells were all terrible, so they literally would only have time to heal", and I feel like the devs may have taken that with some level of seriousness. generally for any source of damage I'm having to doubleweave OGCDs, because none of them ever really seem to cut it by themselves.
shields are flimsy enough that an immediate pepsis is still pretty likely to fail and waste the skill entirely.
if you're not using multiple things (and metering out your damage mitigation buffs appropriately) AND the tank isnt managing all of their defensive cooldowns, any tank not wielding an axe is likely to just keel over dead at any time in dungeons (and even fates sometimes). i realize this is at odds with the similar bullet point in the Good section, but this refers to the 'famine' part of the situation.
-most buttons are generally the same: the DPS spells are all pretty similar in speed, damage, and range and all fight for the GCD, making them all feel rather interchangeably worthless, especially in single target situations like bosses and trials. this contributes to...
-still no downtime activity to speak of: with all the non-healing buttons seeming more or less identical, they're all basically the same button you spam when healing isnt needed (such as when a white mage is present).
-pneuma just feels bad: the large shiny 'sells-the-class' move is basically a dosis/toxikon + (effectively) zoe-buffed ixochole in one button (minus the MP recovery), with a cast time for cinematic effect. while you can't zoe an ixochole normally, you could use that same GCD to do the same combination of actions for the most part. thats... not really a great capstone.
also seems to snapshot the healing oddly early, making precasting it rather tricky/easy to waste for some enemy attacks (particularly ones that are delayed after the cast bar ends, like the final story trial's raidwide attack).
-charybdis and living dead still exist: the scholar problem, but worse.
-having damage reduction bundled into a heal is weird: in most cases, you'd want the damage reduction BEFORE the hit (wasting the heal), or what you're healing with those skills don't have a follow-up attack within the damage reduction's duration (wasting the DR). taurochole at least pretty freakin great for big pulls tho, since you generally want both the heal for current damage and the DR for the rapidly incoming damage.
[The Things I'd Consider Changing]
-spice up pneuma somehow: it being your third 330 potency non-choice (and outclassed by phlegma that you've had since level 26, which has two charges and is on a shorter cooldown!) isn't a great selling point. maybe make the damage a bit punchier, or give it a stun or damage-down or party buff or something.
-move either toxikon or phlegma to an OGCD (personally i'd say toxikon, since it already costs a resource), both to help add an offensive weaving option for when offense is allowed and to reduce GCD bottlenecking on a bunch of skills that are basically the same
-I'd consider swapping kerachole and holos (remove kerachole's cost and allow it to stack with holos/taurochole, make holos cost addersgall and not stack with taurochole).
taurochole (single target heal+DR) and holos (aoe heal+DR) seem like counterparts to each other (akin to ixochole and druochole), yet currently taurochole specifices not stacking with kerachole, and holos has no ties to the addersgall mechanic and seemingly stacks with either. it seems like a genuine slip-up.
despite my gripes, i'm hesitant to suggest any changes to the healing amounts as time and gear/stat increases could very well address that without any mechanical changes (much like WAR doesn't really hit it's stride until X.3 patch gear arrives for decent amounts of crit to actually use)