...what changes would need to be made?
Cryptocurrencies are terribly unstable and volatile, how would this be addressed?
What other barriers may need addressing?
You would have to issue physical bitcoins backed by a reserve.
This is the only way to have bitcoins used for day to day transactions.
I think only a country with large surplus and substantial assets would be able to do this.
They can protect their citizens from volatility to a certain extent.