Although the End dimension has a boss, and three mobs commonly found there, the end needs a makeover. I suggest this in the form of three new biomes, three new mobs, one new generated structure, two new precious materials, and a load of new blocks.
BIOMES: Feral Forest
The Feral Forest would be a new biomes housing two new types of trees, one new mob, and new vegetation. The two types of trees would be a growing from two types of plants. CHORUS TREE: grows from chorus fruit on top of endiric soil, a new purple/ end grass type. The log would be a dark purple color for the bark but would make a black type of plank, not to dark but like dark oak. The "leaves" of this tree would be a layered texture of natural looking block colored purple called chorus slant. FERAL TREE: A tree grown from feral plant, an item that has a small chance of dropping from a chorus flower. When planted on endiric soil can grow . The slant that would be colored a light grey and the log would be a white color with grey spots in it. The planks would be a white color to contrast the black chorus planks. Tilled endiric soil would be a new type of block that doesn't need to be fertilized by water but by a new liquid called purplafen. The fertile soil would be used to plant feral seeds and chorus seeds that can drop from chorus skyne and feral skyne, new vegetation items that grow on enteric soil. The fully grown feral and chorus crops will drop that type of shard which is crafted into slant.