I am a huge fan of mods that can enhance the gameplay by adding more atmosphere or visual enhancements without being too intrusive!
This one is pretty awesome, it basically does what the title says. Adds a lovely more leafy appearance to all trees, bushes and grass. What I really love about it, is that it also adds little falling leaves for extra nice vibes.
Shaders Mod (BSL Shaders)
This one must be quite obvious, but it just adds soooo much more graphical fidelity to the game. My current go-to shaderpack has to be the lovely BSL Shader by BitsLabLab. It adds a soft and warm tone to the game which I really enjoy. How to: Install Minecraft Shaders and Shader Packs
This mod is probably a classic and for everyone that enjoys atmospheric sound effects, MAtmos is awesome! Whenever you join a multiplayer server or single-player world, MAtmos will search your surroundings and generates a soundscape of natural noises to match, filling out that perpetual silence of Minecraft.
What do you think?
Let me know if you have any additional mods to add to this list! Maybe we can create a minimalistic mod pack for atmosphere enhancing mods