For opening files in external editors, I’d like the option to open files with editors other than the default, like the “Open With” option in the finder. Either a right click option when choosing a file from the list or an option click when clicking on the “Open” toolbar button would work for me.
It’s not currently possible (except via AppleScript), but this is a feature I’m planning to add. Of course, you can change the default editor (for a particular file or a whole kind of file) from the Finder’s Get Info window, and you can drag and drop onto the Dock to open a file using a particular application.