Change terrain generation

Ever since update 1.17 terrain has changed with some stuff that has been removed for no reason at all with no explanation why. Bring back erosion, flat plains, those small water puddles, cave mushroom's, and lastly add deeper oceans, waterfalls and water being able to generate on high terrain, this will make the world more easier to build on and make it more alive and fun to explore (especially the ocean part making water breathing potions more useful)