A few item and mob ideas for utility and immersion

Combining sulphur and coal/charcoal to craft gunpowder.

Crows/ravens (possible a cooperative mob with wolves).

Birds or prey that you can tame and use to hunt.

Ice zombies (as a counterpart to normal zombies, drowned, and husks)

A new armour slot for gauntlets that cover the rest of the arm that is currently uncovered (this may even have its own special enchantment, such as haste, as the leggings have swift sneak).

An update to the witch hut to make it bigger, more detailed, have better loot, possibly hidden rooms, and have a more witchy feel (especially for Halloween).

A new texture variant for chickens that looks like a turkey once the poplar update is finalised.

A lion for the savannah biome.

A tiger/leopard for the jungle biome.

Snow/ice stairs, slabs, and walls.

Apple pie.

A scythe that could have some kind of fortune enchantment to harvest multiple wheat from a single patch of farmland (also useful for Halloween).

Taming and breeding of bats (likely using spider eyes).

Brown bears.