Your analysis is really professional; you covered most of the techniques. Great!
Here I'd like to remind you of the meaning of pun--one word which has two "dictionary" meanings. In this sense, tone is a pun, because it refers to both the color tone and the tone of voice.
That's why I don't quite understand it when you said-- "There is 'pun' in these words." The images have connotations, or they, together, are symbolic.