A proof-of-work or proof-of-stake system are the only known ways to stop someone from running a lot of client peers or hatchers in a decentralized system in order to block transactions or double-spend. I do not see any new solution to the Byzantine Generals problem in your answers.
What about a "unique node list"? As employed by Ripple.
https://ripple.com/wiki/Unique_Node_ListThis Quora answer describes the Byzantine General's problem well:
The Byzantine Generals' Problem roughly goes as follows: N Generals have their armies camped outside a city they want to invade. They know their numbers are strong enough that if at least 1/2 of them attack at the same time they'll be victorious. But if they don't coordinate the time of attack, they'll be spread too thin and all die. They also suspect that some of the Generals might be disloyal and send fake messages. Since they can only communicate by messenger, they have no means to verify the authenticity of a message. How can such a large group reach consensus on the time of attack without trust or a central authority, especially when faced with adversaries intent on confusing them?
http://www.quora.com/Bitcoin/Is-the-cryptocurrency-Bitcoin-a-good-ideaObviously if you change the problem so that generals can trust certain other generals or messengers or outside "unique nodes", you can "solve" it. This is how banks and ripple solve it. Bitcoin's breakthrough was solving the problem with no trust by using a proof-of-work system. If a coin does not use POW, that means that there is centralization/trust involved. Emulah doesn't seem to understand this concept very well.