It would be really handy to be able to define the list of selectable languages for the backend in the Config.cfc.
Right now all available languages are displayed with english always being on top (the default).
If only one language is then defined, the dropdown would never be displayed and the defined language is always used - very good for french-only or german-only sites.
Of course if english is omitted and there is a missing french/german translation, the fallback would need to be the de-facto default language - which is hardcoded english anyway.
In the current default skeleton the Config.cfc has the following setting
settings.default_locale = "en";
This does not work as it simply does not exist. The correct setting would be
i18n.defaultLocale = "en";
But it makes no sense to change it to "de" or "fr", as this assumes that the default i18n property files are in that defined language. And as no one is ever going to change all of those, the hardcoded default will always be english - even though it might not be selectable (if the above gets implemented)