While there really isn't a "correct" corporate culture, an agency should strive for what makes the most sense for its business. The values the firm proclaims as its own must match those it practices. It should possess a clear idea of what the culture is, what values are rewarded, and how that is communicated to future employees.
When interviewing a candidate, questions that reflect corporate culture are important to determine that individual's values. For example, if creativity and innovation are important ...