Superhero (Marvel/DC/etc) uplift fiction - aka using powers to improve humanity rather than (or in addition to) beating up bad guys

There's almost always really awesome tech, magic or powers in Superhero fandoms that offers numerous ways to improve the lives of humanity as a whole... but the superheroes use it to beat bank robbers or something.

In canon this is so the world doesn't move too far away from real life and remains relatable. A world without climate change or one where cancer has been cured isn't relatable.

I'm looking for fics where the MC focuses on uplifting humanity (or at least those they care about) with the tech, magic or powers they have access to themselves or that they stole from super villains.

Anyone got any suggestions in this vein? I prefer longer fics (60k+) not one shots. Very long and/or completed fics are even better.