In my quest to make clerics of different gods actually feel different, I came up with the following, inspired by the Elemental Turning available to certain domains.
Variant turning - Clerics may replace the standard ability to turn or rebuke undead with the ability to turn creatures based on alignment. Using this option, the cleric may turn creatures with the alignment subtypes for the opposing three alignments of their god, and rebuke creatures with the neighboring three alignments. For instance, a cleric of Abadar (LN) who selects this option may turn creatures with the Chaotic subtype, and rebuke creatures with the Lawful subtype. A cleric of Desna (CG), however, would turn creature with alignment subtypes that sum to LN, LE, or NE, and could rebuke creatures with subtypes that sum to NG, CG, or CN.
If a cleric selects only one alignment domain, then they are choosing to emphasize that value over all others, and the ability to turn based on alignment changes appropriately. For instance, a cleric of Erastil (LG) who takes the Good (but not Law) domains has decided that the Good/Evil divide is much more relevant than the Law/Chaos divide, and turns creatures as if Erastil was NG.
A cleric of true neutral deity who selects this option may turn creatures with the 'extremist' alignment subtypes (that is, LE, LG, CE, or CG), but they take a -2 on their turning check. They may also turn creatures with one alignment subtype, but take a -4 on their turning check.
Paladins may also choose to turn based on alignment rather than turning undead. However, Paladins always turn as if their deity was NG, unless they are multiclass clerics, in which case they turn according to their cleric ability.
If a deity offers elemental domains, their clerics may instead replace the standard turning ability with the ability to turn elemental creatures as described in the granted power of those domains.
Due to this option, the granted powers of the elemental domains are being changed. Instead of granting elemental turning, they now allow the cleric to cast spells with the relevant descriptor at +1 caster level (in the same manner that the alignment domains currently do).
I like the idea of a good cleric intimidating fiends, or chaotic clerics directly opposing Inevitables. However, as anyone who's had a cleric take both the Air and Fire domains knows, there is such a thing as too much turning, so a given cleric can still turn only one thing (Undead, Alignment, or Elements.)
I submit this to Paizo for consideration.
Thank you.