A few ideas:
A path block that could increase movement and prevent rock, trees and so on from spawning
Fence: to the animals that have spawned also needs a fence gate for you to acces it
fedding tray to heal animals
Mountain biome with more stone and ore spawning and a mine entrence to a undergroung mine biome with higher gem drops and monster spawn
magical fores biome/island with new trees that drop hardwood that could be used in crafting. mobs in the biome could be gnomes that could drop usefull stuff or be befriended and help with mineing. on the island there could be mushroom log that spawns mushrooms with 3 stages 1. where it's just a log 2. 1 mushroom drop and 3. with 2 or 3 mushrooms dropping.
Sakura Asian inspired biome/island maybe like a zen garden
and last a log cabin to heal you through the night and speed up time
Hope some of it could be of help or inspiration :D