Here's what I think and will be modding for myself at least.
Disasters that can be avoided or minimized by the appropriate Mana:
Dustbowl, Washed Out (roads): Water
Tornado, Hurricane, Monsoon: Air (Not that something like a hurricane could be destroyed, but more like it's guided away and/or buildings are protected).
Cyclone: Air or Water (it's a tornado made of water).
Pestilence (Insect Swarm): Nature (like summoning bird flocks to eat them)
Food Sickness (unit can't move): Life "I'm getting better..." ala Monty Python.
Events that specific civilizations/religions should have unique reactions to:
Spoiled Grain: (Rats) Clan of Embers goblins should just eat the rats instead, reducing food loss by one-half.
Jackpot: Council of Esus city religion "See? Everyone has a chance to strike it rich!" Gambling House plus Gold and/or Culture.
Immigrants, Antelope, Famine, Healing Plant, Farm Plows, Farm Bandits, Orphanage Fire: Not for Infernal. (In some rare and not so rare cases they could)
Joyous Wedding, Wedding Feud, Baby Boom, Left at Altar, City Split, Sobs (Murdered Wife), Ransom (daughter), Governor Assassination (son survives): Not for Infernal or Mercurians.
Angelic Procession: Not for Infernal or Ashen Veil.
Heresy: Grigori should see this as proof that religions are useless since they can't agree even when using the same god, and get a Golden Age.
Werewolf Morality (Chose 1 or 5 dead): With your tweaking of the Doviello, possibly receive 1 Ravenous Werewolf? Not for Infernal or Mercurians.
Ice Sculptures: Illians receive a Golden Age.
Waters of Life (oasis): Malakim receive a Golden Age, no Infernal at all.
Horseshoes: Hippus Golden Age.
Experienced Captain (Naval): Lanun Golden Age
Esteemed Playwright: Balseraph Golden Age
Moneychangers: Khazad Golden Age
Corrupt Merchants: Council of Esus state religion "Right methods, wrong targets" receive a Golden Age
Angel of Mercy: Empyrean state religion "Take heart from this in these troubled times" receive a Golden Age.
Miracle (at Walls): Include Illians. Mercurians "Proof of the righteousness of our cause" receive a Golden Age.
Master Smith: Luichirp Golden Age
Favorite Son (Gladiator): Doviello "Proof that the strong shall survive" Golden Age
Events that should also take affect in the corresponding Hell terrain:
Dustbowl, Tornado