option 3 is the most relevant to the statement above
Sadness: add a slow violin solo
Happiness: make it quick with light notes
Anxiety: make a slow part of the symphony, then suddenly add in a quick and high note every so often
It would be 2D art due to the flat surface area of the side walk. but if you have very good art skills you can make it look 3D
For the audience to get a better visual?¿