Negative Update

They could add a new negative layer to the Nether, like the Overworld up to layer -64. In this deeper area, there would be special structures where a new material called Netherium would be found. It's more durable than Netherite, but very difficult to obtain, making it very exclusive. The End could also have negative layers up to -64, where ancient End skeletons would be found, and new biomes like the Violet Forest and the Amethyst Forest would be found. In the latter, a new crystalline mineral would be obtained to improve Elytras, making them more durable and unique.