pre-defined field for subtitle; language-specific headline capitalization


Unfortunately, there is no pre-defined separate field for the subtitle, which I do not really understand as some publishers demand a period between the main title and the subtitle, others prefer a colon or semicolon.

So it would be important to have separate fields for consistent output regarding punctuation.

Obvisouly the title-subtitle-separator should not be added if the title ends in a “?” or “!”, etc.

I know that I can of course use the secondary or tertiary title field for subtitles but this will produce (I think) incorrect formatting when I switch to another output style which uses the field for other purposes. So this would make my library incompatible with all available styles.

If I use a custom field I will get into trouble with headline capitalization if I understand correctly that headline capitalization applies only to the (primary??) title field of a chosen reference type.

And – last question – is it still not possible to designate different capitalization schemes for different languages (see also here) and to choose which fields the schemes should apply to?

Thanks for your help!