Board Thread:Suggestions forum/@comment-26119768-20170814202524/@comment-29680750-20170815150555

This reminds me of this old mod: http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/1287082-1-6-x-1-5-x-1-4-7-underground-biomes-forge-smp (Give it a try)

Perhaps something similar could be in order, though with nicer textures.