So magic is wild and unpredictable in Hekinoe, and it effects changes upon the user.
Hmm, just had a thought. I'm always bothered by all the Fell Heritage and Warped Flesh feats. The reasoning for them is that magic does weird stuff to living creatures. It is why Fallen, Soulless, and Rankethlek don't have to take Warped Flesh feats if they are spellcasters, they're not living creatures. However, the weird thing is that all these nasty fleshwarping mutations do beneficial things. If I could do it over again, I'd keep the Warped Flesh and Fell Heritage feats but not make the Warped Flesh feats mandatory for spellcasters at first level, but I'd also try to implement some sort of taint system. Not sanity like in Jason's campaign, but taint where you start looking icky and being icky and maybe get an icky aura that makes normal folks vomit and sends animals scurrying away from you. All this icky would not be beneficial to you, the point is that there is a cost to sorcery and that cost is icky and unreliable. I dunno, never really thought about it before, and that isn't what this post is about anyway.
Back to the matter at hand, magic is wild and unpredictable in Hekinoe. There are various places where if functions in a more stable fashion or in a completely stable fashion like in Orcunraytrel, but there are also areas where it is completely bat shit crazy uncontrollable to the point where the rate of misfire percentages you find in The Known World Campaign Book are doubled or tripled. Casters in these areas, to my mind, would possess a greater amount of control, skill, and luck to wield magic without dying messily.
My thought is that a caster growing up and learning magic in a more wild area would have an easier time casting spells in a more stable area. For instance, Karl learned magic in The Known World. Granted, magic became easier to control between The Rebellion Arc campaign and the aborted Psychogenic Fugue Arc campaign, but only by shaving 1% off the misfire chances, so it isn't really a big noticeable change. So Karl grew up in The Known World where magic is tough to control and he diligently learns to do so. Then he goes to Orcunraytrel where magic is apparently stable and does not do things like give extra limbs and huge eyes and that sort of thing. By comparison, magic is easy in Orcunraytrel. Since he has all this experience controlling spells with great difficulty, wouldn't he have more energy and focus to devote to his sorcery now that it isn't trying to knock him around and slip out of his control?
What I'm am thinking is that a caster from a higher unreliability area who moves to an area with a lower unreliability area shaves additional percentage points off of his misfire chance. Don't have the exact system worked out yet, but nothing extravagant, and there will always be that no lower than 1% misfire chance rule regardless of where you are casting a spell (except in special cases like Orcunraytrel). A caster from an area with a misfire chance the moves to an area that has no misfire chance, like Orcunraytrel, adds a +1 to his caster level. Finally, a caster who moves from a low misfire or no misfire chance area to an area with a higher misfire chance, increases his misfire chance by a small amount. There would also be feats you can take to kind of work off that excess misfire chance so you could simulate your character becoming accustomed to the wilder magic of an area. Or maybe traits, traits might be better.
Fucking magic. I hate magic. Psionics are better and cooler. I'd take a Soulknife over a Magus any day of the week.