Enderman farms would be pointless as the end resets, they would only be useful for about a month. But everything else I totally agree with! I have been struggling to get diamonds (Yes I know there are good ways to get them but I am not a fan of constant grinding) and end cities are a perfect way! (Plus all the Elytras which is the reason why I need diamonds, I just love flying around my builds and zooming through the air) And Shulkers just make building so much easier.