I recommend two of the most common failures with simple solutions:
- Allow ZIP file uploads of XML files, then unzip and start. This will prevent many hosts who do not allow large file uploads to allow designers/developers to import easily.
- Allow import to continue from an XML/ZIP files already uploaded previously (if failed), rather than starting a new upload again
- Allow continuation of the process if partially completed, e.g. especially when importing remote media and timeouts could occur. Again, if hosts do not allow timeout settings to be changed.