It would help me if I could give a new file a custom name, before I even (have to) save it. A "(re)name file" option next to the "save (as)" option would do. I could create a number of files then from within NotePad++, only having to organize and name 'em there instead of having to do this afterwards when I have already saved the files. If I do that, I have to re-open these files again when I have changed their names. (There is not yet a file-renamed recognition in NotePad++. It perceives renamed files as deleted.)

The same goes for existing files. I might want to change their names when opened in NotePad++ before I first save them again (as... with the new file names). When a filename has changed in NotePad++, just as when the file has never been saved before, the file should be marked as changed. (You may even want to remember the original name, to be able to unmark the file if it hasn't changed and is renamed back to its original name.)

It may also be convenient to create each new file with a customizable name, instead of simply "new #". Possibly the name could be built from a number of (other) fields like username, creation date/time, current directory etc.