People love to bash nu-SMN for it's lack of complexity as compared to it's previous versions, but I'll take that on one of the healers if the DPS don't want that design, it's got three phases it can shift around to suit the fight's mobility requirements, and that's two phases more than the current healers have. Also, DNC is a good thing to bring up, as it's fulfilling the exact idea that I want to see from healers: easy to get into, fun to optimize and rewarding when you do so. Of course, healers don't need to have all those procs like DNC does, but as I've said before, I find it hilarious that DNC is better at AOE mit than WHM is
It is admittedly quite a niche situation, but as Rein mentions, holding Lilies for Inviolate Purgation in P7S was helpful. From my own experience, I was thinking of J-Waves in TEA, where I would use one Lily to heal at the start to keep the timer ticking, then move to MP costing heals, going from Med2 for the regen, to Medica1, to Med1 with PI, to Rapture to prevent overcap, to Cure3 with Thin Air for zero MP cost. Being able to juggle two independent resource costs is something I would not really like to see removed, as a merge of Rapture and Medica1 would do. However...
The reason I suggest Medica1 upgrade via trait to Medica2, is simply the potencies. Medica1 (after lv85 with the trait) is 400p. Medica2 is 250, plus 150 per tick for 5 ticks (totalling 1000). This means that, after only a single tick, Medica2 is equal potency to Medica1, with 4 ticks left to burn, for only 100MP more. Might as well make the trait, have Medica2 be 400p base potency, and 4 ticks of 150 (so 12s duration instead of the current 15). Additionally, I think a good idea would be for SE to move the 1-50 CLASS skills (which includes Medica2, as it is the CNJ 50 skill, where Benediction is the WHM 50 skill) down to the 1-30 levelling experience. This way, the early game has more buttons available to players who get synced, certain jobs get key mechanics sooner (eg MRD would have Storm's Eye, and learn about it's buff management, no later than 30, whereas atm it gets it at 50, meaning it has to use it's AOE move in singletarget to apply the buff, very scuffed), some jobs get AOE much earlier, etc. It also opens some room in the 30-50 bracket of levels for some additional skills to be learned (eg if we move some 'Job actions' to 'Class actions' and rescale them, eg DRG's Doom Spike AOE)
TLDR, I'd move the trait upgrading Medica to Medica2 down to 30 at the latest. Potency of the regen can also be adjusted if needed (eg make it 300p on cast, plus 100 per tick for 12s, totalling 700) and increase it's power at later levels. As for FreeCure, I wouldn't mind it moving to Stone. However, if I had my way, FreeCure would also change. After all, if we have Cure1 trait-up to Cure2, then FreeCure's effect becomes 'when you cast Cure2, you have a chance your next Cure2 is free', which sounds like it might actually get some use in high-heal-pressure scenarios. But yes, do the trait upgrade, and then just make Stone AND Cure2 proc it. We don't want to use Cure2, so we might as well make the times where you DO have to use it, less punishing (costing only damage, instead of damage+MP).
As for my suggestions, thanks. I notice that a fair amount of people seem to agree with, if nothing else, at least my stance that 'something needs to change'. As a great example of what I mean by 'design space opens up for the devs to work with' re: my design ideas, literally just came up with this: you could have Stone/Glare have, say, 20% chance to proc FreeCure. But, the cast of Quake (the empowered form of Stone/Glare after using the gauge spender) could be guaranteed to proc FreeCure
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SCH is wild, it's got some stuff at 15, some at 20 and some at 30y, it's all over the place. Meanwhile, SGE is able to hit someone standing in the next instance over with Kera/Physis/Panhaima/Holos, and WHM's Temperance being 50y is able to reach so far it can actually reach the other add platform in E8