Another small trick (for GS 3.0).

In Page Management ("View all pages"), list subpages (children) of a parent sorted by date instead of page title.

Edit /admin/pages.php line 42. Change this:

$pagesArray[$count]['sort'] = $parentTitle .' '. $data->title;

to:

$pagesArray[$count]['sort'] = $parentTitle .' '.str_pad(strval(2147483647-strtotime($data->pubDate)),10,'0',STR_PAD_LEFT);

That's for descending (newer first). If you prefer ascending order, change to:

$pagesArray[$count]['sort'] = $parentTitle .' '.str_pad(strval(strtotime($data->pubDate)),10,'0',STR_PAD_LEFT);

(Note: Parent pages will still be sorted by title.)