We think it would be great if before going on vacation (or even if an admin can do it to) you could be able to mark your account as Away on Vacation for a set period of time (until JJ/MM/YYY) for example. The expected behaviour would be that nobody can assign new issues to you, and issues that are currently assigned to you get marked with a flag depending on settings you put in place on the project (ie if person is away, bounce issues back to Project Owner for example).