Note : I will be going into additions and potential changes to every domain that I think could use it.
Air : Gains Air-Stream, Gains Expedious Retreat on Cooldown, Gets Gust of Wind at L4, Same buff as Air-Genasi, Cannot be knockdowned by Gusts of Wind/Weather effects (Could also gain Air-stream book air-ele early 1/day)
Animal : Gains Shapechange at T9, Loses True-Seeing at 3, Gains Animal Companion at level 3 scaling at 1/3rd Cleric Level (L30 gets a L10 AC for RP purposes) - Gets Animal Empathy as Skill
Death : Gains PM Scaling for undead (Summons 2 w/animate dead, ect) Can cross-class into Palemaster w/scaling for Divine spells as well as Arcane. - Gains Enfeebling Ray (T1 spell) infinite/day as-if GSF necro-wizard/sorc
(BONUS) - Add Scaling to "Neg-Plane Avatar" Turning it into a worthwhile "Henchman" style Undead / Death Avatar
Destruction : Re-named to CHAOS Domain, Gain Slaad-Summon Stream + Red Slaad 1/day early-levels, Scaling as a semi-summon / "perma" Gate, though Weaker (SLAAD ONLY) - SUPER BONUS : Gains "Chaos Surges" for divine spells?

(Wild-Clerics anyone?)
Earth : Gain Earth Domain - Gain Greater Stoneskin at T6, Stoneskin moved to T3, Gains Bombardment at T8, Gains Stonehold at T5 (Also could gain Earth-stream book Earth Ele early 1/day)
Evil Domain : Gain Infestation of Maggots at T2, Gain Blasphemy 1 Tier lower, Gains Yugoloth Stream, Planar Summons come out as 1T higher up to Gate w/gains slightly buffed stats
Fire Domain : Gains Fire Stream, Gets Flame Weapon T2, Incindiary Cloud, Fireball, Flame arrow/Firebrand, Inferno/Combustion, (Gets Fire-stream book Fire ele 1/day)
Good : Gains celestial Stream book summon, Gains Bless/Prayer turn/level (or hour/level, extended duration) Gains Good Hope 1 level earlier, Gains Planar-summons 1 Tier higher up to Gate, which gets slightly buffed stats
Healing : Great as-is, Would maybe say if anything, Gets SF Heal at like, level 5? and ESF Heal at 30
Knowledge : If SF Divination is taken, Gain GSF Divination for Free, Power Word Stun/Kill at T7/9 respectively? (Could also give SF/GSF Lore at certain levels)
Magic : Cleric levels count at 1/2 for Arcane caster CL, T1 Gain Shield. T2 Gain Magic Missile, T5 Replace Icestorm with LESSER isaac's missile. T9 Gain Isaacs Greater Missile Storm - Gain SF/GSF spellcraft? could be too strong.
(Bonus) Gain a Familiar at 1/3rd Class level (L30 has a Level 10 familiar for RP purposes)
Plant : Entangle at T1, Vine Mine at T5, Camo/Mass Camoflage at T1 and T4, Gain Natures Balance at T9 (Potential Re-name to Nature Domain, If possible add Animal to Turn list w/Vermin too)
Protection : Shield at T1, Premonition at T8, Gain "Divine Ward" Feat, allowing a +1 Guard akin to PDK. Mind Blank?
Strength : Scrapped, Added to War - REPLACED WITH
Law Domain - Hold Person, Hold Monster, Gains LAWFUL Stream, Summons planars at +1 Tier up to Gate which gains minor buffs, Gets a small-lawful esque summon for low-levels. Gets Outsider Turning. Possibly gains Bigby Spells
(PRAISE THE) Sun Domain : Turning strength increased (as normal) Gains Sunburst, Undeath to Death, at -1 Tier, DC for Sun-based spells increased by +4. Gets infinite Light /day. Gains Blindness/deafness and Mass Blind/Deaf, loses cleric status is putting on sunglasses
NEW DOMAIN : Darkness Domain : Gains "Free" Shadowdancer-crossclass As-if Shadowmage, HiPs at L20. Gets Darkness at -1 Tier, Shadow Conjuration spell-line, Sneak attack at every 5/levels? (so at 30 would have 5d6 sneak attack)
Travel Domain : Great as-is, Possibly get Ride as a Skill, or a 10% speed bonus like Barbarians. T9 Spell Mass-Haste maybe? (too strong?) Maybe just add Impossible to fail Rope-Checks and Climb-Checks -- Possibly a % bonus to language-Learning or A bonus language at level 10/20/30 (To learn) or 15/30 (to learn)
Trickery : Already great, I'd possibly say If SF Illusion is taken, gain GSF Illusion for Free. Possibly too strong. Perhaps SF/GSF Bluff or a bonus to Conversation Skills
WAR/STRENGTH : Battle Mastery is excellent, Gain Power-attack for Free (possibly) - gain a free Weapon-Focus?, Honestly this domain is strong as-is. I'd just possibly give some bonuses to animal-buffs, but possibly restrict summoning.
Water : Gain Water-Stream, Gets Drown at T6, Iceburg, Cone of Cold, (Small water Ele from stream-book at early levels), Wall of Ice, Freeze
LUCK DOMAIN : Gain Luck of Heroes, Gain +1 Unisave at L 7/14/21/28 (+4 total), Chaos-Shield as-Wildmage spell, On-Summoning can do Nothing, Gain -1 Tier, gain +1 Tier (stacks with GSF Conj).
Commerce Domain : Gain Skill focus and ESF Appraise at Level 3 / 20, Charm Person/Monster, Dominate Person/Monster (paying them off) at T1/4/6/8 Gains 1K Gold per Month (Like old Gift of Wealth), Protection from Spells, Merchants always act like your favoured race.
That's all I can think of At the moment without it needing new/more Streams, Like if there was a "Wild-Beast/Magical Beast" Stream that Animal-Domain could get for free.