6. Lack of government support prevents mainstream use.
what's a "Government" oh you mean the guys that work directly for the people that issue the currency in to Debt?
the people that issue the currency into Debt are by default the leaders (in most cases) of the government.
next question:
Why would entities that issue debt money ever support ANY debt free system that means they lose all control over the "ongoing mechanics of debt issuance" ?
the answer is they won't and you are living in fantasy land if you think they will (just because.)
if they look like they are supporting it, its because they are either 1. actively destroying it. or 2. working towards that.
You would probably trust having your money stored in a bank account. Would you trust having your cryptocurrencies stored in a MtGox?
The EU for example could issue a regulated cryptocurrency:
* Low incentive for hoarding (high currency flow)
* Low volatility (stable value short-term)
* Stable in terms of inflation and deflation
* Decentralized
* Peer-to-peer
* Block chain with encrypted user IDs/wallet addresses (so that the coins don't have to be cold stored)
* Zero transaction fees (low friction)
* Miners that are run by the EU member states as a public service
* Fast and reliable transaction times
* VC Protocol regulated by EU authority
* User ID system regulated by EU authority