My summer programming was different from my normal school year programming in two ways: I had an outdoor storytime in addition to our regular indoor storytime, and I included one additional program per week - a performer, a movie, an event on the library lawn, etc. etc.
When it came to our finale, I had a few options. With the construction happening right outside the library, it wasn't really feasible to hold the program on the library lawn or in the library itself. However, National Night Out was August 1st this year, so we simply scheduled our finale to occur within the regular National Night Out events our city was already going to hold.
This means there was food, drones to watch, games to play, music, and other items going on - none of which I had to plan myself. I was only responsible for the library's table at this event, and we brought back the teens and their excellent face-painting skills because the teens and the kids both enjoy it and we already have the face paint, brushes, etc.
I would call this event a rousing success, mainly due to the small amount of planning I was responsible for at the very end of a long summer.