The current ‘File Navigation Pane’ uses a flat-list in order to display the file contents. When projects grow in size/scope, this is seriously annoying cause files which you don’t use often become an annoyance (they are in the way). When the project grows, the file count can become quite large and makes navigating from one file to another a challenge.
I would suggest that you ADD the option to view the files in some sort of tree-mode (tree view), such that nodes are collapsible within folders. Exactly like a typical windows file tree.
This could be an optional mode for those who prefer a flat view like is currently implemented. So that one can choose to view in flat mode or tree mode.
Additionally, you may even want to add a section which lists the top 5 or 10 most frequently used files for quick access. In my case, this would probably be very helpful since when I work, I will often work with the same few files for a few hours.