Many possibilities exist. In addition, one should add the best of one's own slides, particularly if the show local conditions in one's own town or area. It is usually also an excellent idea to add some astronomy images, either near the beginning or at the end or both.
All audiences appreciate such slides.
We call the problem light pollution. Pollution is something made by mankind that threatens mankind, either all of us or some of us. Glare never helps visibility, yet it is much too common. Some people actually believe that there isn't any light unless there is glare, because we are so used to seeing only bad lighting with its associated glare. Light Trespass is someone else's light that bothers you.