I think I already know the answer to this, but wanted to make sure there wasn't something obvious I'm missing. Is there a quick way to update the drop down selections in forms, rather than one by one? For example, we are working on standardizing our Country field so it matches our CRM system list (don't ask why this wasn't already happening previously ), I'm hoping I won't have to go through all of our forms and individually update each field.
Not saying this would qualify as "quick" for you, but the REST Asset API could be used to update the form descriptors on the server.
Or you could also leave everything as-is in as far as Form Editor is concerned, then use the Forms API (that's the browser-side JavaScript API) to update the select lists. It's kind of the same pattern as localizing a form in the browser, where the Form Editor shows the default language but all the translations are done in real-time in the browser.