Well, I guess I just need to get that Mac Plus/SE/Classic and give it a whirl. I'll look into IP Net Router on the CC to help share the mounted volume from the older Mac.

As for iPhone remote, I have no worries using it. It's simply a fancy web service for Mac OS X. You have to do some port mapping for security, and you set your own password for the service. It's not tied into your admin account (unless you make it the same). The whole thing runs local, the developer is not involved in anything.