Rick's Default (Requires Optifine)
This pack aims to fully immerse players in the charm and experience of vanilla Minecraft by making the biomes more lively.
Full of new plant and animal variants, bringing unity to the environments with connected textures, and a sense of adventure to the game with exciting refreshed item textures, before long you will forget this isn't vanilla Minecraft and you'll never want to go back.
Please provide feedback in the comments, it helps a lot!