New mounts and mobs variants

-Frozen Zombie and Stray riding a Zombie Polar Bear

-Dirty Zombie and Bogged riding an Infected Slime

-Piglin riding a Hoglin

-Underwater Skeleton

More mobs would increase diversity and consistency. Desert biomes have desert skeletons and zombies, while winter and swamp biomes only have skeletons, and underwater biomes only have zombies.

An infected slime could quickly crawl forward instead of jumping. An infected slime could drop an infected slime ball, which could be used to create a potion that grants an effect that prevents jumping. An infected slime ball could also be used to create an infected slime block. This block could have a unique function or be identical to a regular slime block.

I think there is plenty of time left to add mobs that would only differ in textures, drops, and sounds.