I like that you can create your own folders...
It bugs me there is not a button to collapse all the folders though. Never bothered me that much until we started recently working with gigantically complex CAD models. I have several models in one scene and need to copy all the materials from one car to the other. Pretty annoying to have to find the tiny little scroll bar and scroll all the way to the top and then collapse all the folders again by hand.
:)
Inside the scene tree, right click and select "Collapse All".
I really like the "collapse all" in the scene tree, but instead of collapsing all the way down to base set of folders: Models, Cameras, Scene sets, I wish it would stay expanded to the root level folders within those 3 folders, as that's where I'm looking to immediately navigate from after collapsing. Maybe a preference setting, or could you add another option to "Collapse All" called "Collapse 1st Level"?