I have been in end city's before, this is what I remember that's in them!:
Well the 2 bullets I just stated are found in a room in a tower. This tower, is a huge basically pipe with end rod and (some) block parkour. It is hard because there is a ton of Shulkers that infinite shoot you with their (I like to call them) "cores". There "cores" are balls of white that give you levitation when hit. It is hard because When they hit you, you have 3 seconds to get to a end rod or block before you have to start over again. So, as I was saying, There are bridges to rooms that you get to from the tower. Again, guarded by Shulkers. In these rooms have more, Shulkers that have a chest. In that chest have the Enchanted Armor and Weapons (I believe all new and no about to break stuff) which I think is pretty OP stuff.
How to get elytra? Well there is only 1 in the whole end city's. There are a few end ships floating around. No one can be specific of what end ship has the elytra. So, in the random chose end ship Go to the basement, and there is a item frame that has only 1 elytra on it. Grab that, and you just had a incredible vacation to the End!