1.12-Type Custom World Generation Options

Please add a 1.12-style customization menu to allow for more pre-1.18+ world generation.

The custom world was one of the best things about 1.12, and it has since been removed and never addressed again, even though it was once said that it would come back. (This has not happened)

Please re-add the ability to use sliders to create custom worlds, remove/adjust caves, and further control the world generation.