Comment by gloomyday

I've had this problem for a long time. My solution was to keep my organization as flat as possible. This means everything insurance-related would go to 13.

A flat structure seems less organized, since you are “mixing” stuff, but as long as there isn't too much stuff inside, going through stuff one-by-one is faster than you think. If I do have a lot of stuff in a section, I either split into several sections in the top structure (so 13 is life insurance, 14 is other...), or go one level deeper (not preferred, but I do it when it's very clear and there is too much stuff, like photos, which btw sorting chronologically works best for me).

It is really not much of an issue having 50 top sections. It makes the organization transparent, and indexing, sorting and going one-by-one remains easy.