Making some estimates on power. Ignoring the +1 anomoly.

Cure
Scaling for tier 3: 20
Cure at cap 2: 45
Power at cap 2: 200? (somewhere between 198 and 218)
Max cure: 65
Power for 2 > 3: (65-45) * 20 = 400
Power at cap 3: 600?

Cure II
Scaling for tier 3: 20
Cure at cap 2: 130
Power at cap 2: 400
Max cure: 145
Power for 2 > 3: (145-130) * 20 = 300
Power at cap 3: 700

Cure III
Scaling for tier 3: 5
Cure at cap 2: 260
Power at cap 2: 300
Max cure: 340
Power for 2 > 3: (340-260) * 5 = 400
Power at cap 3: 700

Cure IV
Scaling for tier 3: 2.5
Cure at cap 2: 520
Power at cap 2: 400
Max cure: 640
Power for 2 > 3: (640-520) * 2.5 = 300
Power at cap 3: 700



Cures 2, 3 and 4 seem to cap at 700 power. Cure 1 caps at 600 power. No data to make a guess at cures 5 and 6 yet.

This is different from the current formula, where all cures reach cap at the same power (1240).


Old cap reached at: 400 skill, 250 mnd, 250 vit.
~~ (250 mnd + 400/5 skill) * 3 + 250 vit
== (250+80) * 3 + 250
== 990 + 250
== 1240

New cap reached at approximately: 496 skill, 270 mnd, 270 vit.
~~ 496 skill + 270 mnd * 5 / 9 + 270 vit / 5
== 496 + 1350/9 + 270/5
== 496 + 150 + 54
== 700

or

598 skill, 135 mnd, 135 vit.
~~ 598 skill + 135 mnd * 5 / 9 + 135 vit / 5
== 598 + 675/9 + 135/5
== 598 + 75 + 27
== 700



Aleste's graphs of Cure IV indicated another inflection at about what would be 300 power. So its progression would be like:

Min power: ??
Cap 1 power: 300
Cap 2 power: 400
Cap 3 power: 700

With scales of:
Scale 1: 2.0
Scale 2: 10/7 (1.429) (originally estimated, corrected to exact value)
Scale 3: 2.5

That means the amount cured at cap 1 should be: 520 - ((400-300) / 1.42) = 450

That matches the test data from Aleste. So...

Amount cured at:
Min: 270
Cap 1: 450
Cap 2: 520
Cap 3: 640

However that implies that the power required to reach cap 1 is at least (450 - 270)*2 = 360, when we're only at 300 power.

The above Scale 1, 2 and 3 are all verifiable as 2.0, 10/7 and 2.5, respectively. Therefore there has to be a fourth tier at work.


Given that the difference between Min and the above Cap 1 (450-270 = 180) is much larger than the difference between the other caps, we have a fair bit of room to work with in making a preliminary estimate. In the current model, the scaling rate is 1.0 for the very first tier for most spells, so I'll find a value set that matches that.

Revised:

Min cured: 270 HP
Min power: 40
Tier 1 scale: 1.0
Cap 1 cured: 370 HP
Power to reach cap 1: 100
Total power at cap 1: 140
Tier 2 scale: 2.0
Cap 2 cured: 450 HP
Power to reach cap 2: 160
Total power at cap 2: 300
Tier 3 scale: 10/7
Cap 3 cured: 520 HP
Power to reach cap 3: 100
Total power at cap 3: 400
Tier 4 scale: 2.5
Cap 4 cured: 640 HP
Power to reach cap 3: 300
Total power at cap 3: 700

I chose a min power of 40 to match a rough scale of min power of 10/20/30/40 for cures 1/2/3/4, similar to the current model. Obviously all of this needs testing to find the actual values, but the progression seems pretty clean.

What we see is an initial fast gain (1.0 scale) that slows down (2.0 scale) as it approaches the cure capability of someone subbing a mage job (thus ~150 skill and maybe around 250 power). It then speeds up again after power passes the 300 mark (10/7 scale), followed by another slowdown (2.5 scale) for the highest levels.


Testing the lowest end will require the no-subjob trick and the no-skill trick.

For the no-subjob trick, described here.
For the no-skill trick, as I understand it, you need to get the moogle to set your job level (41 whm for cure 4), and then choose one of the teleport options without exiting the menu. This should prevent auto-capping your skills.

Together this should put your total power in the 30-ish range. From there you can do minor tweaks to merits and such until your cure amounts start going above baseline.



As an aside....

Currently I cure in.. 88+40 mnd, 80+3 vit (from what I remember offhand). Light Arts puts me at 404 skill, plus 35 skill in gear. Total power would be approximately 526.

Assuming that's roughly in the neighborhood of a normal average-to-good build, that would put typical cures at about:
Cure 1: 60, 90 with 50% potency
Cure 2: 135, 200 with 50% potency
Cure 3: 305, 460 with 50% potency
Cure 4: 570, 855 with 50% potency





Checking the same with Cure III, but assuming 4 tiers to start with:


Min power: 20?
Cap 1 power: 170?
Cap 2 power: 200?
Cap 3 power: 300
Cap 4 power: 700

With scales of:
Scale 1: 2.5?
Scale 2: 1.0?
Scale 3: 2.5
Scale 4: 5

Amount cured at:
Min: 130
Cap 1: 190?
Cap 2: 220?
Cap 3: 260
Cap 4: 340


Much more difficult to make good guesses here due to lack of low-end data.