Sometimes the best way to make an image seem lively is to add people by photo-editing them into place. In the examples showing the Jetport renovation that is just what we did.
Photo-editing people in to place presents many challenges to producing a natural looking result. The perspective has to match, the lighting has to match, and the source photos need to have the right style to go with the illustration. So travelers dressed comfortably with luggage for the airport
It is nice to have some people prominent and some people in the background. Both buisness and casual dress could be found in a hospital cafeteria.
Business suits and business casual for the conference room and shorts and t-shirts for the gym.
This last one uses the people and the existing pier in the foreground with a 3d model and rendering of a second story addition in the background. It's a delightful bonus to have great scale figures and entourage in the base photo for an illustration.
There are other situations where 3 dimentional people are better. The prime reason to use 3d people is for efficiency where several views of the scene get to see the same people from different angles. That would be hard to do with static photos.