Please let me know what you think!  You can see some of my thoughts and processes over here if you're interested: https://realtimevfx.com/t/flyings-sketch-book/19952
Updated Version
Old Version
Texture Set 1
Texture Set 2 For the clouds/swirls, I used a shader to blend 2 channels together to try for a more stylized look.
Older Version Video
Mesh Cloud