Monetization could be a consideration too. Do they want the feature to generate revenue? For example, a premium feature for advanced reviews or a subscription-based movie library.
Another thing to consider is the target audience. Who uses the website? Casual movie viewers, critics, or a mix of both? The feature should cater to their needs. For example, if it's for casual users, maybe a social feature is better, while for critics, in-depth analysis tools could be more useful. jex movie website link
I should also consider technical feasibility. Some features are easier to implement than others. A simple feature like a search bar is straightforward, but a recommendation system with machine learning would be more involved. The user might not have mentioned resources or time constraints, so it's important to suggest something that's both useful and achievable. Monetization could be a consideration too