Very late game dimension

Many people have thought about the deep dark portal opening into a scary sculk dimension or just not opening at all. I think that one thing that minecraft is missing is more late game things. Sure you can go defeat the other 2 bosses, the wither and the elder guardian it just wont last long. I think that within the end dimension you can rarely find a special item that will open up the deep dark portal opening into a sky dimension. Similar to the aether mod. Inside of this dimension we could find auto crafters and many other op things (still very rarely) these items would be protected by other boses. Well how are you gonna beat these bosses if the wither was a challenge in max gear? Well inside of this dimension 2 things could happen. You could find a tamable dragon very rarely or you could hatch the dragon egg. I am aware the dragon egg is as a trophy but whats a better trophy than your own dragon? The deep dark portal would be big enough to take it out with you anyway.