Break natural leaves while you ride a horse

Removes baby zombies

Revamps the core mechanics and removes the bad features

Removes EXP and revamps the enchanting system

Removes copper, with iron replacing it in the few "uses" it has.

Craft a bed with mixed wool colors

Removes Granite, Diorite, Andesite, Tuff

Removes infested blocks

Repair elytra with leather (and disable phantoms)

Endermites don't spawn when using Ender Pearls