Taking a step back, to look at the bigger picture.
Int Wis and Cha casters can sooner or later cast whatever.
Con is Psi Evocation and Miracle = anything.
Str is Psi Transmutation and Shapechange casting = nearly anything.
Dex is Psi Teleports and Disintegrate, the most restrictive.
X stat to Y bonus, has every single category of changing
main stat use, which means it's certainly possible.
Some of the ToB abilities change a stat too, already.
"Beat The Snot Out Of Them" sounds like a
not-Good aligned 2nd level divination equivalent.
This just got posted a board over :
A bit late, but the "Lost Tradition" feat from the Bastards and Bloodlines book by Green Ronin can set your casting ability score to any of which you choose - even if it would not regularly be capable of casting spells, such as Strength or Dexterity. That said, Charisma from Wisdom based spellcasting is not asking too much if Dynamic Priest is out of the question; it is also a direct upgrade as well to that aforementioned feat.
