The idea looks good in general but I think one of the reasons so many people is turning towards the cryptocurrency thing is to avoid fees and reduce transfer times.
If i am to decide for myself too, i need a place where i can transact with less fee as compared to other crypto markets. Basically, thats the main purpose of cryptocurrency to help make payment system more easier and cheap.
They could still be fast and cheap. Because they are a bank doesn't mean they will be slow! I love the idea in theory but in actuality I think a fiat bank can implement this system first because of the infrastructure they already have in place. Would love to see an ICO this year that actually pursues this, yet due to regulations incoming I highly doubt it will work or have any significant impact.