In terms of the arrangement of characters in the novel, that is, the aesthetic requirements, why did the author portray Lin Daiyu and Xue Baochai as two completely different characters?

In terms of personality, Daiyu can be said to be a bit Taoist, while Baochai is a Confucian. Daiyu is real and natural, and her career economy is meaningless to her; Baochai is resourceful, considerate and pursues success in the secular sense.

From the appearance, Baochai is like spring flowers, rich and beautiful; Daiyu is like autumn chrysanthemum or hibiscus, with sadness in beauty.

On Baoyu's birthday, there was a girl draw lots. Baochai painted peonies and Daiyu painted hibiscus. For Baoyu, spring flowers and autumn flowers have their own beauty, which is worth cherishing and appreciating. He cherishes every girl.

Only in Baoyu's heart, Daiyu is his confidant, and their intimacy is beyond Baochai's intervention.