The way an audience reacts to different characters can change depending on the cast. In this play it could be interesting to experiment with ages. Consider how differently an audience might feel about a young, lively Beatrice compared to a much older version. Neither option is right or wrong. Each invites different questions and responses.
In the video extract, the director invites the actress playing Beatrice to perform the masked ball scene in different ways. In one version Beatrice knows that Benedick is behind the mask and so we see her teasing him. Alternatively, she could be deadly serious, not knowing that it's Benedick she's talking to.
These performance choices are important as they affect the way the audience views the characters and their relationships.