How does Nick characterize the guests at Gatsby's party? What does his descriptions tell us about how Nick feels about most people? What sense of the Jazz age do we get from his description of the party?

Nick becomes an observer rather than an active participant. Nick is repulsed by the shallow superficiality of the people at the party. THe people have no other interest other than money and the illusion of happiness rather than happiness itself. The Jazz age, at least for the filthy rich, is a world of consumption and flat characters.