Built a spreadsheet for handling gear comparisons for magic damage, since that's been bugging me lately. It's in my usual Google Drive folder:
here
On the Gear page it shows the damage (or damage per MP) value for all tiers of all elements, so you can see how damage is affected across the entire range of spell options. It highlights the better of the two gear sets' damage in green.
Notes:
1) Uses the new magic formulas (currently on the test server), not the current ones.
2) Is set for any of the four major nuking jobs: Blm, Sch, Geo, Rdm. Because of this, gear isn't guaranteed to be usable for the currently selected job. Account for that if building gear sets.
3) Still lots of things missing. Doesn't handle Meteor/Comet/Impact/Kaustra/Helixes. Doesn't handle Blm AF3 set bonus.
4) Doesn't account for resistance rates (though it does have magic accuracy field in place for later).
5) Doesn't yet account for a real "DPS" value. Fast Cast field is in place for future calculations.
6) Doesn't account for Magic Burst damage, or gear boosts for that.
7) Handles Magical critical hits and Conserve MP proc averages. Handles MP savings for Dark Arts (or costs for Light Arts).
8) Does account for MP savings of Seidr body.
The exchange rate between Int and MAB varies widely across spell and element tiers. In the new formulas, the higher the spell tier, the more MAB is favored, and the closer you get to the Thunder line the more MAB is favored. The opposite is true in the other direction.
For AM and AM2, MAB is almost always preferred. For anything else, the majority of spells tend to favor Int, for the typical values you can get in any given slot.
The 'lower' elements (Stone, Water, Air) are significantly more MP efficient than the 'higher' elements (Fire, Ice, Thunder). At the extreme ends, Stone tends to be 40% to 50% more MP efficient than Thunder (not counting the first tier singles or -gas, where Stone/Stonega is 3-7 times more MP efficient than Thunder/Thundaga).
There are four 'tiers's of Int. dInt of less than 0 (currently uses the same value per point of int as the 0-50 dInt tier, though this hasn't been validated); dInt between 0 and 50; dInt between 50 and 100; and dInt between 100 and 200. dInt above 200 doesn't add any additional damage.
Example:
In the 0-50 dInt range, For Stone V, 10 Int ~= 12 MAB; for Thunder V, 10 Int ~= 6 MAB.
In the 50-100 dInt range, For Stone V, 10 Int ~= 8 MAB; for Thunder V, 10 Int ~= 5 MAB.
The old rule of thumb for 2 Int ~= 1 MAB gets completely thrown out the window, except maybe for Thunder V and a couple nearby spells. On the Stone side of things, it's closer to 1 Int ~= 1 MAB at tier 5. At lower tiers, it can be more skewed towards Int -- 1 Int ~= 2 MAB to 1 Int ~= 4 MAB. Optimal nuking sets change from spell to spell, though there's a trend over the entire grid.
Augmented Soothsayer and Lehbrailg staves beat out Magian staves for large swaths of spells, partly because often you'll want to use Int instead of MAB, so the multiplying factor of Magian staves' affinity has less to work with.
It will be interesting seeing how people will manage gear sets after this change.