Both are similar assets in that they represent an asset held outside the beaurocracy. However, currently gold in not outside of beaurocratic and central bank influence as cryptocurrencies are (but don't be surprised to see central banks beginning to acquire cryptocurrencies so that they may attempt to control it as well). One main difference for me is that it is probably dangerous to have gold in your possession in the wold we live in today. Also, ease of use and fractionality, as you suggested, are huge advantages for cryptocurrencies.