Three ideas, actually.  Simple ones first and the hard one at the end.

Could we have a facility to sort the displayed list with the,
- main P[rogram at the top,
- then all the S[ubroutines,
- then all the F[unctions?

Could we have a facility to suppress either filenames or program/subroutine/function names in the list? 
I ask this because I tend to keep all my routines in separate source files and to give each source file the same name as the program, subroutine or function that it contains.  The file outline/project tab therefore displays a list in which everything appears twice.  I'd like to be able to suppress one of each pair, and only switch them both on when I actually need to see a list of all the routines in each of my source files.

Now for the hard one.

It would be just terrific if Simply Fortran could,
- scan all source files,
- compile an internal list of all prog, subr and function routine names in all files,
- re-scan all files looking for calls to subroutines and functions that it knows about,
- display the project structure with subrtine & function names in indented lists under calling routine names.

That's all I, er, ask!
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John