How does the author make the character of the father memorable in "The Fly in the Ointment" by V. S. Pritchett?

"The Fly in the Ointment" by V. S. Pritchett is a short story that tells the story of a meeting between father and son on the day the father loses his property due to bankruptcy. The son reluctantly goes to check on the old man and gauge his needs, but the old man seems fine with his lost fortune.
When we first meet the father, we are expecting a hollow man who has lost everything. Instead, we meet a powerful man who gleams with pride: “He was a vigorous, broad man with a pleased impish smile.” This is a stark contrast to the son, who is “round-shouldered and shabby, a keen but anxious fellow in need of a hair cut and going bald.” This contrast gives the reader her first glimpse that there may be more to this father than meets the eye. The author seems to delight in negatively contrasting the boy with the father.
Also, the author shows often that the father has many sides to his personality that the son has discovered over time: “His father, then a dark-haired man, talking in a voice he had never heard before, a quick, bland voice, to his customers.” This is a voice he heard when just a boy, but as they talk, he sees a new side to his father:

“Listen to me a moment. I want you to get this idea,” said his father, his warm voice going dead and rancorous and his nostrils fidgeting. His eyes went hard, too. A different man was speaking, and even a different face.

The son seems to have only one dimension, while the father seems multifaceted. We even learn that he may be a felon, “and the son, startled, found himself asking: Were they telling the truth when they said the old man was a crook and that his balance sheets were cooked?” This gives even more depth to the character of the father.
Lastly, the loss of the business has inspired the father to care nothing about money, since he has none now. He has accepted what has happened and has decided to act from this moment in time. However, when the son mentions he might be able to raise money, the father seems very keen to raise some capital himself. This changeability seems intriguing and a bit scary for the reader. The father is not a character that you immediately trust, but you can’t help picturing him boldly proclaiming while his son sits and simpers.