Snapdragyn
Explorer
Yay, time for another of our favorite topics! 
The purpose in this thread is to discussion specific issues in removing alignment from D&D. Please forget the 'it isn't D&D' stuff, the 'alignment works as is' stuff, & the 'alignment works as is if you really read the rules' stuff. I agree that alignment simplifies many of the things I'm going to be writing below. I'm interested in the less simple version (the simplicity of alignment comes at a cost of moral ambiguity which I miss in D&D) and particularly in the thought exercise in removing alignment without negatively impacting game balance. If you enjoy rules puzzles, welcome!
CLASSES
In many cases, class alignment restrictions can be replaced with detailed 'codes of honor'. Penalties for breaking these should be the same as for alignment restrictions in RAW. Obviously it can be argued that alignment is a simpler shorthand for these codes of honor, but that isn't the point of this thread.
Barbarian
Currently: Non-lawful.
CHange to: Perhaps a 'code of honor' that would reflect the 'savage' nature of the class? 'Never let someone insult you', um... what else?
Bard
Currently: Non-lawful.
Change to: A bardic 'code of honor'? Um... eat, drink, & give Eric's grandma conniption fits?
This one probably stumps me most of the classes. Frankly, though, if lawful rogues are allowed I'm tempted to let it pass for bards as well.
Cleric
Currently: One alignment step from deity.
Change to: Allow any (see the Eberron Campaign Setting) or have each church or deity enforce a code of behavior . Mixed system possible (some churchs/deities could be more strict, others could be lax & plagued with corruption).
Druid
Currently: Any neutral.
Change to: As broad as that is, I'm very tempted to not worry about it. Perhaps use clearly developed expectations of the specific deity instead, similar to the second option mentioned under clerics above.
Paladin
Currently: LG.
Change to: Replace with detailed code of honor specific to the knightly order.
Monk
Currently: Any lawful.
Change to: Replace with detailed code of honor specific to the monastic order.
CLASS ABILITIES
Casting Spells of Opposed Alignment -- Spells no longer have alignment. Some spells may have effects which violate specific codes (e.g. a deity of healing may consider inflict spells to be a vile corruption of her divinely granted powers).
Cleric & Paladin Auras -- Gone. Serves no purpose without detect & protection spells AFAIK.
Detect evil -- Gone. The point is, after all, to get rid of the glowing red target circles.
Ki strike 10th level -- See DR below.
Turning or Rebuking Undead -- Depends on the deity; some may grant turning, some rebuking, some either with the player choosing at character creation as per neutral clerics.
Smite evil -- Allow smite to work against any opponent. Alternatively, different orders could smite different classes of creature (aberrations, outsiders, etc.); this option probably represents a greater restriction than the base rule, however, so should be considered carefully.
SPELLS
Blasphemy -- Replace alignment-based effects with deity-based effects? (This modification would work best in campaigns with few deities.)
Bless/Curse water -- Replace the alignment-based effect with banishing type (see DR below) or allow each to effect all outsiders equally.
Bless weapon -- Replace with banishing type (see DR below).
Detect <alignment> -- Gone.
Forbiddance -- Replace the variable damage by alignment with DM-adjudicated variable damage by intent. Those actively wishing to kill to the caster receive 12d6 damage; possessed or controled beings or those wishing to capture the caster (but not capture in order to kill later) receive 6d6 damage.
Hallow/Unhallow -- Modify the magic circle effects as per the spell or replace with deity-based effects.
Holy/Unholy aura -- Hrm. Not sure on this one.
Holy smite/Unholy blight -- Allow to affect any, as per smite in Class Abilities section.
Holy sword -- Replace the extra damage against evil with a banishing type (see DR below) or allow it to effect any enemy. Modify the magic circle as per that spell.
Magic circle against <alignment> -- See protection from spells below.
Protection from <alignment> -- Should not just disappear. Allow to work against any 'enemy'?
Summon monster -- Allow any creature from the appropriate level list or devise specialized summoning lists (see UA for guidelines).
OTHER MECHANICS
DR/<alignment> -- DR is a key balance component for many creatures. Simply removing this would change the difficulty of the encounter. Replace each DR alignment type with a 'banishing' type (i.e. 'fiend-banishing' for DR/good, 'angel-banishing' for DR/evil, not sure of names for DR/lawful & DR/chaotic 'banishing' types) The banishings would work against any creature having the matching DR regardless of the creature's actual type, but would not have any effect on creatures who do not have the matching DR regardless of the creature's alignment entry. For example, a +1 'angel-banishing' sword would overcome the DR of a deva or an archon equally well and deal an additional +2d6 damage to each (since each has the 'DR/evil' special quality); it would have no effect on a gold dragon beyond being a +1 magic weapon (though gold dragons have a 'good' alignment entry they do not have the 'DR/evil' special quality). Because this change reduces the power of aligned weapons, cost of each should be reduced to +1 bonus.
Whew! Yeah, it's a lot to change. Obviously I would not adopt such broad changes without thoroughly discussing it with players first (particularly for developing class-based codes of honor, where player input would be essential both for mutual understanding of the ramifications of breaking the code & for player satisfaction with the chosen class). There are some areas where I'm not sure quite what to do, & I'm sure I've missed some spells (heck, I found most of the ones I listed just looking for one that I'd already thought about).
The purpose in this thread is to discussion specific issues in removing alignment from D&D. Please forget the 'it isn't D&D' stuff, the 'alignment works as is' stuff, & the 'alignment works as is if you really read the rules' stuff. I agree that alignment simplifies many of the things I'm going to be writing below. I'm interested in the less simple version (the simplicity of alignment comes at a cost of moral ambiguity which I miss in D&D) and particularly in the thought exercise in removing alignment without negatively impacting game balance. If you enjoy rules puzzles, welcome!
CLASSES
In many cases, class alignment restrictions can be replaced with detailed 'codes of honor'. Penalties for breaking these should be the same as for alignment restrictions in RAW. Obviously it can be argued that alignment is a simpler shorthand for these codes of honor, but that isn't the point of this thread.
Barbarian
Currently: Non-lawful.
CHange to: Perhaps a 'code of honor' that would reflect the 'savage' nature of the class? 'Never let someone insult you', um... what else?
Bard
Currently: Non-lawful.
Change to: A bardic 'code of honor'? Um... eat, drink, & give Eric's grandma conniption fits?
Cleric
Currently: One alignment step from deity.
Change to: Allow any (see the Eberron Campaign Setting) or have each church or deity enforce a code of behavior . Mixed system possible (some churchs/deities could be more strict, others could be lax & plagued with corruption).
Druid
Currently: Any neutral.
Change to: As broad as that is, I'm very tempted to not worry about it. Perhaps use clearly developed expectations of the specific deity instead, similar to the second option mentioned under clerics above.
Paladin
Currently: LG.
Change to: Replace with detailed code of honor specific to the knightly order.
Monk
Currently: Any lawful.
Change to: Replace with detailed code of honor specific to the monastic order.
CLASS ABILITIES
Casting Spells of Opposed Alignment -- Spells no longer have alignment. Some spells may have effects which violate specific codes (e.g. a deity of healing may consider inflict spells to be a vile corruption of her divinely granted powers).
Cleric & Paladin Auras -- Gone. Serves no purpose without detect & protection spells AFAIK.
Detect evil -- Gone. The point is, after all, to get rid of the glowing red target circles.
Ki strike 10th level -- See DR below.
Turning or Rebuking Undead -- Depends on the deity; some may grant turning, some rebuking, some either with the player choosing at character creation as per neutral clerics.
Smite evil -- Allow smite to work against any opponent. Alternatively, different orders could smite different classes of creature (aberrations, outsiders, etc.); this option probably represents a greater restriction than the base rule, however, so should be considered carefully.
SPELLS
Blasphemy -- Replace alignment-based effects with deity-based effects? (This modification would work best in campaigns with few deities.)
Bless/Curse water -- Replace the alignment-based effect with banishing type (see DR below) or allow each to effect all outsiders equally.
Bless weapon -- Replace with banishing type (see DR below).
Detect <alignment> -- Gone.
Forbiddance -- Replace the variable damage by alignment with DM-adjudicated variable damage by intent. Those actively wishing to kill to the caster receive 12d6 damage; possessed or controled beings or those wishing to capture the caster (but not capture in order to kill later) receive 6d6 damage.
Hallow/Unhallow -- Modify the magic circle effects as per the spell or replace with deity-based effects.
Holy/Unholy aura -- Hrm. Not sure on this one.
Holy smite/Unholy blight -- Allow to affect any, as per smite in Class Abilities section.
Holy sword -- Replace the extra damage against evil with a banishing type (see DR below) or allow it to effect any enemy. Modify the magic circle as per that spell.
Magic circle against <alignment> -- See protection from spells below.
Protection from <alignment> -- Should not just disappear. Allow to work against any 'enemy'?
Summon monster -- Allow any creature from the appropriate level list or devise specialized summoning lists (see UA for guidelines).
OTHER MECHANICS
DR/<alignment> -- DR is a key balance component for many creatures. Simply removing this would change the difficulty of the encounter. Replace each DR alignment type with a 'banishing' type (i.e. 'fiend-banishing' for DR/good, 'angel-banishing' for DR/evil, not sure of names for DR/lawful & DR/chaotic 'banishing' types) The banishings would work against any creature having the matching DR regardless of the creature's actual type, but would not have any effect on creatures who do not have the matching DR regardless of the creature's alignment entry. For example, a +1 'angel-banishing' sword would overcome the DR of a deva or an archon equally well and deal an additional +2d6 damage to each (since each has the 'DR/evil' special quality); it would have no effect on a gold dragon beyond being a +1 magic weapon (though gold dragons have a 'good' alignment entry they do not have the 'DR/evil' special quality). Because this change reduces the power of aligned weapons, cost of each should be reduced to +1 bonus.
Whew! Yeah, it's a lot to change. Obviously I would not adopt such broad changes without thoroughly discussing it with players first (particularly for developing class-based codes of honor, where player input would be essential both for mutual understanding of the ramifications of breaking the code & for player satisfaction with the chosen class). There are some areas where I'm not sure quite what to do, & I'm sure I've missed some spells (heck, I found most of the ones I listed just looking for one that I'd already thought about).