Sorry, I was under the impression that you already had a system worked out. You are very sensitive, my friend. You are not going to make it long on this forum. Have you heard of the Freedombox Project? https://www.freedomboxfoundation.org There was discussion in that community of backing up private keys through a distributed p2p network, which sounds similar to your system. The idea was to distribute pieces of a private key to friends in one's network (perhaps through Diaspora). If the friends don't all know each other, or know who else has parts of the key, then they can't reconstruct it, but your client can. I don't know if they got around to implementing it. The main difference from your idea is that you control all the servers while theirs is a decentralized p2p system.