1. Beatrice says that the purpose of the simplicity in her town's design is to help them forget themselves. The Abnegation have dull hairstyles and wear dull clothes, and they only eat dull food. They try to keep everything dull because they believe that forgetting yourself makes it easier to be selfless, as vanity causes selfishness.
2. When Beatrice is talking to Caleb, she hears the whistle of a dauntless train in the distance,and says that "it sounds like the Dauntless, calling me to them." She realizes that she wants to be free, and that she doesn't want to give up the part of herself that makes her Beatrice Prior. From this you can infer that she will most likely transfer to Dauntless at the choosing ceremony.
