When you check country by country, you can see how much is still remaining. If you zoom to low detail, you can see picture details.
Sure WikiLovesMonuments is an awesome project and it produces a lot of high quality images of notable cultural heritage.
But I will take this opportunity to remember a little known tool/project, Commons Coverage. The motto is "Imagine a world in which every single free image is surrounded by other less than 1 km far away."
Exploring the United States map, I have found a user who has been taking many pictures of roads and streets. Or looking at Norway map, we can see that somebody took pictures while on a plane.
Of course, this requires to attach coordinates to every picture you take, though improvements in technology is making this easier.
Time for a WikiLoveStreets or something at that scale?