This is a crazy idea but we need some form of unique physical form of ID or way of signing your private keys - say retina scan.
Well every "average joe" that I know has a retina scanner!
All you need for a practically foolproof secure wallet is a computer that never touches the internet and a little effort on the users part.
A savings account that can be accessed if needed. Like buying a safe or renting a safe deposit box.
Put fewer Bitcoins on a spending account that is less secure. Like carrying cash around daily.