I am once again obsessed with @skyscrapergods concept of alicorn ascension.
Just thinking about the rest of the mane six as immortal massive deities.
Applejack, goddess of orchards and agriculture, spreading good harvest of each crop as she walks, turning the seasons with her hooffalls
Fluttershy, goddess of the wild lands and animals everywhere. Wherever she steps, biomes explode into being. Her tears can heal the most grievous of wounds. Her mere presence is what drives the mating seasons of various beasts (as an act of preservation and conservation)
Pinkie Pie, goddess of mirth and joy. Where she walks there is no sadness. She also brings comfort to the grieving with soft reminders of happy memories with their loved ones, not taking their sense of loss from them but merely reminding them of the joy that causes the grief to be so profound, and in so doing, easing it.
Rainbow Dash, goddess of storms and weather. She does not walk the earth but rather the reaches of the sky. The most fickle of the goddesses, the weather changes with her mood as much as for the needs of ponies, and just like she can provide rains in a drought, she can bring storms to calm seas.
And Rarity, most unlike all the rest, goddess of gemstones and craft. She slumbers deep beneath the earth. Her dreams form veins of precious stone and metal, and her nightmares form earthquakes and cave-ins. Her spirit runs through the night, accompanying Princess Luna to provide dreams of inspiration to all those who create with their hands.
(Honestly, I'd love to make a sub-AU of your AU with your permission, credit to you ofc, skyscrapergods. I'm genuinely so obsessed with the concept.)