After I wrote this post I went back and looked at HiveSigner and immediately remembered why I don't like it and don't use it. I just didn't want to put any of my keys in that first screen.

So you're right, I won't be adding it. HAS and Keychain are 100% all I need right now.

I'm wondering if I should run a mirror of your HAS server. Do you think this could be put behind a load balancer? I can see there is an issue with state between calls.