Archiving accounts \ requesters \ technicians

I have raised this before but had no response. Is there a way - and if not, can it be added to the feature list - of archiving accounts \ requesters and technicians? The drop down selection list becomes very cumbersome if we have to scroll through every account \ requester \ technician that has ever existed on the system.

Example: last week a customer rang up asking why their request had not been progressed. When I looked at the reference this was because the request had accidentally been assigned to an inactive account. So, human error caused this but it was an avoidable human error as if the non-live account was not in the drop down list, it could never have been selected!

These don't have to be deleted but could have a tick-box for inactive which marks in the DB and then precludes them from being shown in the active lists.