I want a solution which can give me something approaching the confidence I have in precious metals under times of stress.
I say that when (not if) there is another financial crisis of the type which (according to legend) incited Satoshi, and it cannot be controlled with bail-outs and such, it is a near certainty that alternates to whatever solution we are funneled into will be attacked vigorously. This includes gold and Bitcoin.
I say that these attacks are nearly certain to include pressure on corporate internet infrastructure providers and leveraging of the monitoring framworks known to be available to entities such as our NSA.
There is no way to achieve the goal you want through the methods you're proposing.
If you want a currency that can store value, then it needs to be used by other people. That means it has to support the kind of usage levels that you're afraid of.
If remains too small to be effectively attacked, then it will also be too small to retain any kind of monetary value.
Safety through smallness is a dead end, which leaves safety through growth.
That might not work, but staying small for certain won't work.
Gold in modern societies counters your argument, but I agree that wide use is desirable. Not necessarily for security but more for humanity. This is exactly why sidechains are so important. They're promise is a cryptographically strong and thus near perfect proxy for Bitcoin which is then free to hide out. That it hides out significantly under the care of people with the skills to protect it is a good thing and a key to it's robustness. Again, not at all unlike gold.
The sidechains where Bitcoin use flows among the masses are highly flexible to fill a variety of niches (e.g., a 'safe' monitored and controlled currency for use within the mandates of the state.) They are also dispensable which addresses the single-point-of-failure problem. What I never did envision was the crypto methods which could allow individuals using a successfully attacked sidechain to reclaim their original BTC eventually. Brilliant!