Have an option to add the deep dark to existing chunks

So I know that a lot of people would like to have the deep dark load in their existing worlds , but other people are worried it may break their world. So I present a option. Players who would like to have the deep dark in their old chunks should have the option to load the deep dark in existing chunks, if they do so it should make a copy of the world to prevent loss of builds, corruption etc. It would also allow players fix what's wrong in their worlds before trying again. So please, add that to the game, it would mean a lot to me and a huge part of this community.