just to be clear you are aware of the consequences of a blockchain ? :) the memory growth and transaction time is linear all the time? A bank is making millions of transactions a day so they would need Petabytes of data.
Etherium has 200GB after 6 months, and they are pretty slow in comparison. And every party would have to sign everything ;D ... just thinking that 1 troll puts himself behind a 56k modem and what that would mean?
so the consequence of idea behind sharing everything is that you have to share everything and everyone has to agree that is a tedious problem the more things you have to agree on and the more people who have to agree on the slower it will get :)
Just as a thought about the problems of this kind of technology :)