Warning: Long post, lots of math.

Formula for cures:
h = floor(((3*(MND + Healing Magic/5) + VIT) / x) + y) + Equipment bonus) + Day bonus + Weather bonus)

Separating out primary aspects:

((3*(MND + Healing Magic/5) + VIT) / x) + y

Rename for clarity:

((3*(MND + Healing Magic/5) + VIT) / scale) + offset

And will consider the stat aspect as a single entity:

RawStat = (3*(MND + Healing Magic/5) + VIT)

So you can think of the formula as

RawStat / scale + offset

Just for reference, minimum HP healed:
Cure 1: 10
Cure 2: 60
Cure 3: 130
Cure 4: 270
Cure 5: 450


Now the important bits:

Initial offset:
Cure 1: -10
Cure 2: 20
Cure 3: 70
Cure 4: 165
Cure 5: 330

Initial scale:
Cure 1: 2
Cure 2: 2
Cure 3: 2
Cure 4: 4/3
Cure 5: 4/3

"Soft cap":
Cure 1: 20
Cure 2: 75
Cure 3: 160
Cure 4: 330
Cure 5: 570

RawStat required for soft cap:
Cure 1: 60
Cure 2: 110
Cure 3: 180
Cure 4: 220
Cure 5: 320


After the soft cap, scale increases to 4 for all except Cure V, which drops to 1. Higher scale means less gain per mnd/vit/healing skill.

While wiki lists the soft cap in terms of total healed, it would make more sense mathematically to list in terms of raw combined stat: (3*(MND + Healing Magic/5) + VIT). When RawStat reaches a certain value, that RawStat/scale becomes the new offset and a new scale is implemented.


The values that wiki lists for progressing above the soft cap use a "y" (offset) value that assumes scale works from 0. Given that the scale is discontinuous, that's not the best way to present it. It should be more like:

((RawStat - SoftCapRawStat) / newScale) + SoftCap

Cure 1, for example, uses x = 4, y = 5 when applied to the full raw stat once past the soft cap. However if you calculate SoftCapRawStat/newScale, 60/4, you get 15; subtract 15 from the soft cap of 20 and you get 5, which explains the chosen y.

Continuing to the 'hard' cap (though not really a strict hard cap since it can still increase beyond that):

"Hard cap" healed:
Cure 1: 30
Cure 2: 90
Cure 3: 190
Cure 4: 390
Cure 5: 690

The RawStat increase needed to reach the hard cap would be:
Cure 1: 40
Cure 2: 60
Cure 3: 120
Cure 4: 240
Cure 5: 120

Total RawStat needed to reach the hard cap:
Cure 1: 100
Cure 2: 170
Cure 3: 300
Cure 4: 460
Cure 5: 440

You'll note that it takes more effort to get Cure IV up to its hard cap than to get Cure V up to its cap, and that the requirements over Cure III are also pretty substantial.


Then you have the scaling above the hard cap. This scale is the rate at which you need to increase the raw stat total to increase the amount of HP healed by 1.
Cure 1: 114
Cure 2: 214/3 (71.33)
Cure 3: 94/3 (31.33)
Cure 4: 13
Cure 5: 17/6 (2.833)

I'll note that some of the numbers really seem wonky, but I'm not the one who tested them so I'll just accept it. Regardless, they're all extremely high, except for Cure V. Additional RawStat has almost no impact.



Changes that I would make:

Change RawStat required for soft cap:
Cure 1: 60
Cure 2: 110
Cure 3: 180
Cure 4: 220
Cure 5: 320

to

Cure 1: 60
Cure 2: 120
Cure 3: 180
Cure 4: 240
Cure 5: 320

This gives a little more headroom on the fastest-scaling area for cures 2 and 4.

I'd then change the scaling for the soft cap zone from 4/4/4/4/1 to 4/4/4/2/1, giving Cure IV a better scaling rate in that area (keeping the RawStat required to reach the hard cap). The amount cured by each at their respective hard caps would then be:

Cure 1: 30
Cure 2: 110
Cure 3: 190
Cure 4: 465
Cure 5: 690

Which gives a fairly substantial boost to Cure IV, a near 20% increase in amount cured at its cap.

Then look into the post-hard cap scaling. Personally, I'd aim for about +10% cured per +100 RawStat. That would put their respective scalings at:
Cure 1: 33
Cure 2: 9
Cure 3: 5
Cure 4: 2
Cure 5: 1.4


Then the total amount cured at 480 RawStat for each of them would be:
Cure 1: -10 + 60/2 + 40/4 + 360/33 = 40
Cure 2: 20 + 120/2 + 60/4 + 300/9 = 128
Cure 3: 70 + 180/2 + 120/4 + 180/5 = 226
Cure 4: 165 + 240/(4/3) + 240/2 + 0/2 = 465
Cure 5: 330 + 320/(4/3) + 120/1 + 40/1.4 = 718

Which, if you add 50% cure potency, would give:
Cure 1: 60
Cure 2: 192
Cure 3: 339
Cure 4: 697
Cure 5: 1077

Between the caps and the scaling, cures 1-4 gain the equivalent of somewhere around 15%-20% cure potency, putting Cure IV at roughly the equivalent of unbuffed lvl 75 Cure V's, and Cure III at a bit below lvl 75 Cure IV's. In other words, a functionally useful amount cured (over 1000 cured with Cure IV+III) without going overboard into whm's territory.

It's enough to be sufficient for lightly to moderately difficult fights, but still keeps whm as who you want for very difficult fights (shift down the scale depending on quality of mage, tank and/or DD, of course).


That would be my initial suggestion for adjusting healing abilities with an eye towards rdm and sch (with sch getting the extra edge of light weather). After that they can add extra things such as sch's enhanced regens, etc.