We discuss experimental design to study how tailoring text prompts for diffusion models, which generate ad visuals and text, can improve ad effectiveness. The core idea is to use the Twin-2K-500 dataset, a publicly available resource containing detailed demographic, psychological, and behavioral data from over 2,000 individuals, to define nuanced target personas. By comparing advertisements generated with generic prompts versus those adapted to specific persona attributes (e.g., personality traits, values, economic preferences), researchers can measure differences in perceived relevance, persuasiveness, and simulated purchase intent. The design emphasizes rigorous evaluation, considering ethical implications, potential biases in both the data and generative models, and outlining a plan for statistical analysis and interpretation of results. The research aims to understand which individual characteristics are most influential in driving the effectiveness of adaptively generated advertisements.