The Larger Ore Veins: Deluxe combines the Classic, Diamond, and Nether editions into a single data pack as well as bringing lapis and redstone ore generation to match the larger ore vein generation style.
This is a world generation data pack. World generation data packs work best when added to your world during the world creation phase. You can still add them to your world after generating it, you just need to generate new chunks to see the effects.
To modify the size of the ores, go to data/minecraft/worldgen/configured_feature and change the size value in the desired JSON files (The maximum size is 64).
To modify the rarity of the ores, go to data/minecraft/worldgen/placed_feature and edit the count field in the desired JSON files, this number represents the number of generation attempts per chunk.
Some files use a weighted count system, with multiple data values being assigned a weight.
Higher weights increase the chance of the associated data value (or data) to be selected as the count.
With the weight system, there is a <weight>/<total_weight> chance of a particular value to be selected for the count.
In other words, each chunk has 9% chance of making 5 attempts to generate ore blobs, a 27% chance to attempt generating an ore blob once and a 64% chance of not attempting to generate any ore.
A datapack combining all editions of Larger Ore Veins into one