The apartment
The apartment represents home, and it represents frustration, because the size of the apartment makes for difficult, tense living, especially now with three people. Nevertheless, Bin is overlooked for an apartment upgrade. This represents injustice and disenfranchisement because Bin cannot change his circumstances. In a way, the apartment is a trap of fate which he cannot escape until he completes his hero's journey.
The humorous cartoons
The cartoons depict how foolish Bin's supervisors are. But they also represent that symbolically, since the cartoons are evidence that the supervisors are not using the full potential of their staff, because Bin is apparently a very talented artist and cartoonist. People really appreciate his sense of humor too it seems. In the end when he becomes a propagandist, that represents the full potential of his gifts: His art can literally sway public opinion.
The journey toward justice
Beyond using his humor as a way of attaining justice internally (by laughing off his horrendous injustices), Shao Bin also literally journeys to Beijing to find legal justice there for himself and his family. This symbolizes his hero's journey into an unknown world to try and help his family. In the end the journey itself, and his popularity among the working class are what define his success, because the journey impressed the higher-ups at his company.
The promotion
When Shao Bin finally receives a promotion, there is a good aspect and a bad aspect. The good aspect is that he found a creative way to take care of his family in dire straights. The bad aspect is that he is joining the propaganda efforts of big businesses. So, the promotion symbolizes the balance between good and bad, and it represents his forward motion in life through initiative and cleverness.
The artist in waiting
If the reader looks past the obvious aspects of injustice and disenfranchisement, suddenly they can see Shao Bin in a new light. Essentially, he is just a frustrated artist who is overlooked for his talent, because his bosses don't value his gifts. That is a frustration that is universal, meaning that Shao Bin himself represents the frustration of a person unable to do what they love for work.
