Manage collections folder through sub-collections

I have too many Box folders shared with me and they all show up under "All Files". Collections is a good way to organize but I need to have a hierarchy/folder structure for Collections. Currently this can only be achieved through faking a folder structure through naming.

example
Project1
Project1-subproject1
Project1-subproject 2

Being able to create sub collections would solve this.

Currently my Box account is a huge mess of shared folders.