1. Not an option currently requires some code edits
Open Themes/default/Gallery.template.php
Find on line 104
//Show the pictures
$dbresult = db_query("SELECT p.ID_PICTURE, p.totalratings, p.rating, p.commenttotal, p.filesize, p.views, p.thumbfilename, p.title, p.ID_MEMBER, m.memberName, m.realName, p.date, p.description FROM {$db_prefix}gallery_pic as p, {$db_prefix}members AS m WHERE p.ID_MEMBER = m.ID_MEMBER AND p.ID_CAT = $cat AND p.approved = 1 ORDER BY ID_PICTURE DESC LIMIT $curpage," . $modSettings['gallery_set_images_per_page'], __FILE__, __LINE__);
$rowlevel = 0;
Change to
//Show the pictures
$dbresult = db_query("SELECT p.ID_PICTURE, p.totalratings, p.rating, p.commenttotal, p.filesize, p.views, p.thumbfilename, p.title, p.ID_MEMBER, m.memberName, m.realName, p.date, p.description FROM {$db_prefix}gallery_pic as p, {$db_prefix}members AS m WHERE p.ID_MEMBER = m.ID_MEMBER AND p.ID_CAT = $cat AND p.approved = 1 ORDER BY ID_PICTURE ASC LIMIT $curpage," . $modSettings['gallery_set_images_per_page'], __FILE__, __LINE__);
$rowlevel = 0;
2. Currently not an option built I could look into doing in the future. I looked at in the past saw no way to do so without extra queries.
3. That is something I will think about adding in the future.