What does the conversation between Happy, Biff, Bernard and Willy highlight about Willys perception of life? What is truly important to him?

Willy is living in a fantasy. Willy dreams of the American Dream. He wants money, success, respect and the "perfect family". The American dream of course is largely an illusion. Willy refuses to work for whatever fantasy he has. The dream must come easy. Much Willy's ethos rubs off on his sons.

Biff would have wanted to be an All American football star, continuing in the same fashion as he did in high school.

I think Linda would merely dream of stability in her family. Everything about her husband is unstable. This instability seems to infect the whole family.

Happy would like some business success. Much like his father, he wants to live up to social expectations. Like his father, he dreams of being important