The export tool and the import-export app need the ability to keep the folder structure and labels.

After having to restore hundreds of lost e-mails during an account migration I just discovered that the export tool appears to export all emails but not their location (i.e. sent and received e-mails all appear in one folder, and no folder structure whatsoever is exported). Furthermore, the import-export app only allows to restrict an import to a specific time period, but it does not allow to import certain folders from a backup back into the correct destination folders and using the correct source labels.