Custom Page Sorting and Grouping really need to be added ASAP. As someone has said, anything above 5-10 pages and it becomes a nightmare to manage a site…
I’d also suggest adding a special ‘dormant’ pages group , whereby any pages dropped therin are taken out of the live site structure altogether in one single action (drag drop), but can still be worked upon for addition back into the live site pages group at a later date.