“What are the pros and cons of combining different types of messaging (such as wayfinding and advertising) in one display?”
There is always an opportunity to combine different types of messaging within a single display. That challenge it creates is establishing an effective balance (and relationship) between the two formats, which helps the audience. Having worked on programs that combine wayfinding and advertising, I can speak from experience as its help drive engagement with added incentives. There is truth that an audience will engage only if there is something to be gained from it. In this case, they are not only provided direction, but also an incentive through creative advertising to go there. In a lot of cases, there is no gain, meaning the audience is turned off by the engagement simply because it’s all about advertising. There is a narrative that all engagements should follow, and the end result has to leave the audience feeling satisfied. The use of multiple messaging formats will end up confusing the user if there is not an established relationship between the two.