For the gallery I suggest http://drupal.org/project/media_gallery together with http://drupal.org/project/plupload. That should take care of the gallery and multiple file upload problems. I have never tried to restrict access to it, so I'll leave that to you.
 

LOVE IT!!.. Media_gallery is brilliant.. Has a few quirks and lots of dependencies but easily the best solution out there if you can work through it..

Thanks!!