I think this is just fantastic Greg.
I was actually curious why you didn't have any processors or Raspberry Pi involvement or the like. It was interesting to read your design model above.
As I have thought about this type of thing over the years I had thought how cool it would be to have a phone module to plug each phone into that could communicate over wifi or ethernet to a central KSU or possibly Asterisk appliance so one wouldn't have to run 25 pair wire everywhere.
I actually built a 2 line phone system that was similar in function to 1a2 from scratch in the early 80s when I was in jr high school. I still have it somewhere, Ill have to post pics of it. You guys would laugh your asses off but it worked for my dads office!
