I know that tasks can be reassigned, either by the person they are assigned to or through the "Manage" page, however this becomes a daunting task when someone goes on holidays, takes a leave of absence, or is no longer with the company. 

It would be great to be able to either temporarily or permanently reassign a person's tasks, both currently assigned and yet to be assigned. Ideally this would be available both to the user and at an administrative level.

The only other available options I can see are:

• Manually reassigning tasks one by one
• Manually adjusting each business process/workflow that assigns tasks to that person
• Assigning every task to at least two people, so if one is away it doesn't get stuck as pending (although this puts all tasks under "unassigned")
• Assigning tasks to a team (same issue as above)
• Creating a timer event (although this wastes time while you wait for the task to be reassigned)

There should be some sort of out of office setting where you can redirect tasks as easily as you can set up an auto-reply or mail forwarding, without having to completely reroute all of your processes in order to do so.