I don't disagree with you at all - paper money is terrible. However, everything else is worse. The only better option is the complete removal of any kind of barter exchange - like a Star Trek economy - but that relies on a lack of scarcity and automation we haven't achieved yet. We are heading in the right direction fairly rapidly though - completely autonomous mines, factories and vehicles are one of the big turning points of the economy and we are very close to achieving that (50 years optimistically?).