At the moment, it seems like dying just removes your ghost brick and such as part of the default building system. Perhaps what I'm asking for could be refined into a different sort of feature. What about a command that recovers the last duplication you had selected? That way if you lose it for any reason, including accidentally clearing it, you can bring it back.
An extra mile to take with that feature might be to make the recovery persist between client instances, so that you can recover the duplication if say you were to time out from the server. That might be taking it a bit too far, though.