would this be OP?

[Grimoire-M]

I'd only want shields from AST/SCH to stack if they were both nerfed to appropriate levels to compensate and if WHM got an overheal cooldown to help with their lack of mitigation. That would mean SCH would give up Critlo and Noct would have its shield potency normalized to match. Succor AND Noct Helios would both be nerfed to 150 shield potency, which is what it was in HW. Hell I'd be fine if it was nerfed further than that.

The only reason I don't want your exact proposed changes is because I feel that AST should get the stance swap as a pair of cooldowns, not as an always on thing. Having to pick between the two is a meaningful choice and should continue to matter.

The two cooldowns I'd propose are as thus, along with two other notes to help facilitate their use:

1) An Emergency Tactics-style stance swap for the next Aspected spell you cast. Just the swap. No additional benefits. Lasts 15s or until used. 20s Cooldown. Functionally very similar to Emergency Tactics.

2) Take Largesse's 20% healing potency and swap the AST into the other Sect temporarily while benefiting from the healing bonus. No additional benefits. Same 20s duration. 120s cooldown.

3) These abilities stack together, allowing you to get 1-2 spells in your original sect under the healing bonus.

4) Remove the healing potencies on both sects and balance all of the aspected and non-aspected healing spells around a single baseline value. This can be between WHM and SCH in healing potency on the non-aspected spells, and equal on the aspected ones.

[Seraphor]

Not sure why people keep suggesting doing away with ASTs sects. They're the strength of the job and what allows it to synergise with any other healer.

Nocturnal sect nerds a bit of a rejig, but not majorly, and they dont need to, and shouldnt, stack with SCH shields.

They should stack with themselves though, in that a Helios shield (200 potency) and a Benefic shield (500 potency) should stack for a 700 potency shield, instead of allowing you to mistakenly replace a 500 shield with a smaller 200.

[Grimoire-M]

Not sure why people keep suggesting doing away with ASTs sects. They're the strength of the job and what allows it to synergise with any other healer.

Nocturnal sect nerds a bit of a rejig, but not majorly, and they dont need to, and shouldnt, stack with SCH shields.

They should stack with themselves though, in that a Helios shield (200 potency) and a Benefic shield (500 potency) should stack for a 700 potency shield, instead of allowing you to mistakenly replace a 500 shield with a smaller 200.

The fact is no matter how strong Noct's shields are, they don't really solve the problem with AST's lack of passive regeneration in Noct. And the shields don't overwrite if they're from the same player unless the original is smaller. The sect swapping would solve this problem, but I don't think AST needs to have them combined into one overpowered heal. They just need the ability to swap via a couple cooldowns, as I suggested. The ET one covers Fairy-level tank healing in Noct and most shield uses in Diurnal. The Largesse replacement covers O4/8/12S level big heal requirements regardless of what sect you need.

This way the sect you use is mostly a preference thing rather than limiting what the class is capable of majorly. Sometimes you want a Noct Benefic shield in a SCH/AST comp because it's more reliable than Critlo for some busters. The worst that would happen is Noct is used more in prog while Diurnal sees more use in speed runs, regardless of the other healer. Not really a bad thing overall.

[Ghishlain]

Not sure why people keep suggesting doing away with ASTs sects. They're the strength of the job and what allows it to synergise with any other healer.

Nocturnal sect nerds a bit of a rejig, but not majorly, and they dont need to, and shouldnt, stack with SCH shields.

They should stack with themselves though, in that a Helios shield (200 potency) and a Benefic shield (500 potency) should stack for a 700 potency shield, instead of allowing you to mistakenly replace a 500 shield with a smaller 200.

For me personally, the sects are a mark of S-E's inability to design a unique healer concept. Diurnal represents healing like a White Mage while Nocturnal represents healing like a Scholar. It makes it difficult to balance when there are only two healing concepts but three healers. If AST had been a bit more unique in their healing kit, the complaints of healer balance would be different. Right now all we see in the healer balance front is either AST encroaching on WHM or vice versa, or AST encroaching on SCH or vice versa. It's less pronounced on the AST vs SCH front but it's there.

I feel I wouldn't be the only one to think that, because of S-E's design decision for AST's kit, there is a lack of confidence in S-E's design team when they (eventually) pitch the fourth healer for the game.

If they remove the Sects (or made it an active buff instead of a passive buff) and made AST a more vanilla healer with the capability to buff the raid, I would be a lot happier. I feel there are quiet a few people who would feel the same. Maybe not necessarily a vanilla healer with buffs but just something that makes AST more unique than WHM and SCH respectively.

[Bobsmiaw]

If Noct AST needs a passive regen/heal like SCH fairy, how about changing synastry?
So synastry will become a permanent buff on a single target like in PVP (with 10 s CD to change the target).
The effect [Nocturnal]: Heal target with potency 50-100 (to make t even with SCH fairy) every time the AST do an action like benefic, malefic, combust, draw, etc.
The effect [Diurnal]: Give target 10-15% HP shield (stackable with another shield) with 15% change every time the AST do an action like benefic, malefic, combust, draw, etc.

Adding a stance swap as a CD will help Noct AST to compete with SCH whispering down but maybe give it a 1 minute CD?
The effect [Eclipse]: Change AST sect during battle from Nocturnal -> Diurnal or Diurnal -> Nocturnal.
The effect only applies to the next one aspected spell (benefic or helios).

[HyoMinPark]

Why are players concerned with Noct AST having a passive regen? Any situation where you would be in Nocturnal Sect, your would have a WHM in the party (because you’re never in Noct Sect with a SCH because the shields do not synergize). So you would have regens from your co-healer. And nothing in this game does enough outgoing damage to warrant doubling up on regens—even Ultimate. It would just be an overheal doubling up at that point.

[Bobsmiaw]

Because SCH has a fairy which gives a passive healing.
The fairy helps heal the tank and give the co-healer time to dps more without casting regen on tanks especially if the tank only receive auto attacks.
The co-healer only need to cast regen when the tank eats a lot of damage.
Also SCH has fey union which heals more.
This is why SCH became the current healer meta.

[HyoMinPark]

Because SCH has a fairy which gives a passive healing.
The fairy helps heal the tank and give the co-healer time to dps more without casting regen on tanks especially if the tank only receive auto attacks.
The co-healer only need to cast regen when the tank eats a lot of damage.
Also SCH has fey union which heals more.
This is why SCH became the current healer meta.

Regen is used to mitigate the auto-attacks. It’s the responsibility of the regen healer to cast it on the MT to mitigate them.

If you’re casting a Regen to mitigate a large amount of damage, you are healing incorrectly. You don’t use Regen after a tank takes a 60,000 buster; you use either an oGCD to top them up or you cast a GCD heal (Cure II/Benefic II).

[Grimoire-M]

Regen is used to mitigate the auto-attacks. It’s the responsibility of the regen healer to cast it on the MT to mitigate them.

If you’re casting a Regen to mitigate a large amount of damage, you are healing incorrectly. You don’t use Regen after a tank takes a 60,000 buster; you use either an oGCD to top them up or you cast a GCD heal (Cure II/Benefic II).

On the other hand, it's both healer's responsibility to keep everyone, including the main tank, alive. You do feel the difference of not having two regens on a tank in Savage and Ultimate. There are high mobility/AoE phases that you don't have the time to babysit the tank's HP while keeping everyone else alive that they don't want to move into your AoE range for. Precasting two regens on them solves these issues. SCH's Fairies both contribute to this passively at no MP or GCD cost but doesn't get the benefit of getting to regen multiple targets. WHM and Diurnal AST both have ways to do this via their GCD and can multi-regen both tanks in two-boss fights. Whispering Dawn also exists as an AoE regen on a far lower cooldown than Collective Unconscious and Asylum at a strong enough potency to match a WHM and Diurnal AST using Medica II and Diurnal Helios respectively.

If you want to make up for the auto damage, you basically have to sacrifice more GCDs than a WHM would to make up for the disparity in Noct Sect. GCDs you sometimes don't have.

Playing Noct AST in duty finder when the WHM doesn't regen is absolutely awful for this reason. It's worse in Savage because you and the tanks have to make up for it.

[HyoMinPark]

On the other hand, it's both healer's responsibility to keep everyone, including the main tank, alive. You do feel the difference of not having two regens on a tank in Savage and Ultimate.

Even in Savage and Ultimate, you do not need to stack double regens, be it on the party or on a tank—Medica II + Di Aspected Helios is overkill; Whispering Dawn + CU is overkill; Whispering + Di Aspected Helios + CU is definitely overkill (our AST/SCH actually did this for Garuda cleanses during prog and the overheal was 50~60%). It just isn’t necessary. Speaking as someone who has done the content, double regens end up being an overheal more times than not, and any time you’re overhealing means you’re wasting your resources that could be better used elsewhere.

There are high mobility/AoE phases that you don't have the time to babysit the tank's HP while keeping everyone else alive that they don't want to move into your range for.

If people aren’t moving in for heals, that’s on them. Not on you. And it doesn’t mean Noct AST suddenly needs more tools to make dealing with that easier.

For high mobility situations, you either master slidecasting, or you make use of other tools at your disposal (Swiftcast or Lightspeed—the latter of which has made AST better than WHM for fights where you have to do a lot of moving, such as Final Omega).

SCH's Fairies both contribute to this passively at no MP or GCD cost but doesn't get the benefit of getting to regen multiple targets. WHM and Diurnal AST both have ways to do this via their GCD and can multi-regen both tanks in two-boss fights. Whispering Dawn also exists as an AoE regen on a far lower cooldown than Collective Unconscious and Asylum at a strong enough potency to match a WHM and Diurnal AST using Medica II and Diurnal Helios respectively.

Again: double (and triple) regens end up being more of an overheal than not. There is no content that requires you to stack multiple regens to keep the party (or the main tank) alive. Not even Savage or Ultimate, and especially not casual content.

If you want to make up for the auto damage, you basically have to sacrifice more GCDs than a WHM would to make up for the disparity in Noct Sect. GCDs you sometimes don't have.

If you’re a Noct AST, you don’t spam shields to mitigate autos. You pre-shield for tankbusters and AOE raid damage, but you do not spam them. They just aren’t MP efficient. The same goes for SCH and Adlo/Succor. Auto damage should be mitigated by a Regen, which, if you’re paired with a WHM, it is their responsibility to apply. Not yours. If you aren’t paired with a WHM, then you should be in Diurnal Sect yourself, not Noct.

Playing Noct AST in duty finder when the WHM doesn't regen is absolutely awful for this reason. It's worse in Savage because you and the tanks have to make up for it.

And it’s the WHM’s responsibility to regen. If they aren’t doing it, then that is not the fault of a Noct AST. Someone playing a job incorrectly doesn’t mean you need to give another job tools to make up for someone not playing their own job correctly. Giving AST more tools like the ones that have been suggested in this thread will just make it far more valuable in content than WHM, which is already struggling against AST enough as it is (and who has no hope of competition against SCH).

Personally, I call out WHMs that I don’t see using Regen when I’m in Noct Sect. I do not think I need a passive regen a la a SCH fairy to make the healing in Noct easier.