A nice feature to have would be an additional account type: Translator.
With multilingual surveys, sometimes your interviewer does not have sufficient skills in the language that the data analysis will be performed in to translate an answer from the interviewee in the survey language to the export language.
The preference would be for a more complete answer in their native language that could be translated at a later stage, before data export.
This translator account should only be allowed to change text answers and roster names.
I understand completely that this is likely to be consigned to the too hard basket as there are two main workarounds - to reassign the interview to another interviewer account with sufficient translation skills and to translate after data export.
However, this would be a much cleaner workflow and would ensure the translator cannot change answers that they should not be allowed to, potentially losing data.
A common example: Deleting a roster item to re-enter the translated version, thereby losing the information from the roster item, when they should just rename the roster item and retain the roster item data.