The first issue is the download count. In order to have a good download count, you have to make your app known to other people. Normally, the most popular apps are at the front of the list.
Ratings and reviews go together. They depend on the of the use of the app. If your app doesn't have much use, its hard to get decent reviews and ratings to bump your app up on the list.
The number of app page visits can help you get an estimate, but it is not as accurate as the download count.