In my opinion, shulker should be slightly more common to make Ender got more challenge and more fun. Currently, the shulker only spawn in End City which makes them hard to find and the rest of The End is still empty. By making shulker spawn on chorus plant, it makes shulker became more common in The End. This makes The End slightly more dangerous as the shulker can attack player that roaming around floating islands. The player will need to extra careful to prevent getting blasted by shulker while passing through Chorus Plants.
All chorus plant (naturally generated) should have 1 / 25 chance to spawn 1-2 shulker. The shulker may spawn on top of the plant or at the side of the plant.
How can player deal with these shulker? They can break the bottom part of chorus plant and cause the shulker teleport away. Sometimes, it will force shulker teleport down to ground and make them more easier to kill.