If a global pref is wanted, I think a Various pref is a low impact way to move forward, otherwise we add work for translators and use up dialog space. #2176 makes various prefs look a lot cleaner IMO.
Rather than per document, I think a per file type setting would be more useful here. IIRC there's already a filetype setting for default symbol sort mode. As Go uses capitalisation to set symbol visibility, Go might benefit from case insensitive sorting.