Just noticed that the Tenshi and Archangel both have compact gyros. Also, the slope of the "nose", the way the elbows work, etc are all dead ringers for the Archangel. It just needs a PPC in its head, a retractable blade in its arm, and a crazy religious guy in the cockpit.
But yeah, no, this is just the tip of the iceberg. I'm still thinking that the Blakists engineered their own demise, and Devlin Stone and the Republic was just "phase 2" of their plan.