Here's my current model for Intellect -> Spirit regeneration.
First off, assume it doesn't matter whether you are a priest or a druid: the modification is made to the SCALING FACTOR. Everything you compute must be based on that fact.
Druids:
(spirit / x + 14) * 2.5 = regen OO5SR from spirit
Priests:
(spirit / x + 12.5) * 2.5 = regen OO5SR from spirit
If you're computing anything, take off static Mp5, ignore every factor but intellect, spirit, and regen ignoring static factors.
Now, having said that, I used Bekah's numbers for priests for the majority of my high intellect computations, and numbers that Shadowed and I (
http://www.wowarmory.com/character-s...ecrown&n=Mayen) came up with using his character transferred to the PTR. I'm not going to post all the details for now; I have a spreadsheet I'll try to clean up and post later.
Basically, here's the conclusions:
1) Relationship of intellect to spirit is logarithmic. If you have under 300 intellect, you will LOSE regen. If you have over 300 intellect, you GAIN regen.
2) Relationship of factor is quadratic in scaling, to prevent over-scale at the high end.
To find your regen, do the following:
L = - log (int/300)
Factor = Base_factor + (6 L^2 + 7.2 L)
Then (spirit/factor+12.5)*2.5.
I'm not completely happy with the regression curve at the moment, but I'm almost 100% positive that the factor WILL be -log(int/300). The only question is how that factor merges into the actual conversion from your base spirit factor to your actual PTR spirit factor.
The only way to get it more precise is to get a *ton* more data in the range around 300 intellect and down. We need a couple of hundred points in the 110 -> 330 intellect range. Go go.