Would be great to have user defined fields which then export into the various files in an obvious way. An example would be `shortauthor` (a biblatex field for institutional authors).
This won't happen. Not in any foreseeable future. Custom fields create an illusion that those fields are actually usable in a reasonable way. We can't possibly accommodate custom fields when importing metadata from the web, exporting it into standard formats, or creating citations. They're also very difficult to handle when syncing, especially between clients set up with different custom fields as may be the case in a group library.
Seems like you're specifically after an abbreviated author field. This will most likely happen (though also not very soon) as an abbreviation list not tied to any particular item in Zotero database.
And short author functionality has also been implemented as part of the Abbreviation Filter plugin, which is compatible with stock Zotero and available here: http://citationstylist.org
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Seems like you're specifically after an abbreviated author field. This will most likely happen (though also not very soon) as an abbreviation list not tied to any particular item in Zotero database.