Designing and implementing user-friendly wallet backup for the GUI bitcoin seems like it would be a great little project for somebody who knows C++ and knows, or is willing to learn, wxWidgets programming. The non-GUI code already has the 'backupwallet' RPC method, and 'getinfo' will tell you the age of the oldest key in your keypool.
For extra credit, the code could keep track of the last successful backup and warn you that it is time to backup again when the keypool age gets close to the last backup time.