Fabric, 1.21, with Complementary Shaders.

Connective textures related to snow on top of trees look extremely odd, as snow is not as transparent as leaves. This creates a major disparity between the color of snow from the leaf texture, and the snow layer.
Could be fixed with a unique connective texture for snow layers on top of leaves.

The snowed on grass block texture is broken. The Connective textures do not match the grass block texture when there is a snow layer on top of it.
The grassy trim at the top of the block looks odd and out of place - I'm not sure if it's intentional.
The re-use of the snow texture for snowed on grass blocks in cold biomes makes it impossible to distingiush between snowy grass and snow blocks.

I believe this alternate snowy grass texture should be scrapped in its entirety.
The attatched image demonstrates every issue brought up in this post. I'm using O's Colorful grasses in this screenshot, but the issues persist when only shaders and Xi's Enhanced Vanilla are present.

Great texture pack btw. Just think it needs some polishing in this area.