Regarding submarine-launched cruise missiles, I do take a dim view of their "strategic role" - their actual usage (including from subs) in fact being to conventionally-bomb defenseless cities, still filled with civilians, in Iraq: a cowardly act for the world's last remaining SuperPower (after provoking/suckering that country into attacking Kuwait), the start of The Post-Cold-War-Ugliness, v1.0.
And What is The Deal with SUBROC: a weapons system by the late '80s, and advent of the 688s, already at least 30 years old, maybe more. Of all the 688-deployable systems, it is of course the only rocket-boosted-torpedo weapon: a clear and obvious niche. So why, then, have we (read: "I") never heard about any new "Mark"s - or improvement(s) - or anything beyond what I just wrote in a single sentence - about SUBROC? Can this weapon continue to be that secret - still, after all these years - really?
Your description of the BSY-1 sensor suite, and the 688s in general, evokes at least 2-3 decades of spectacular advances in Sonar Research and Engineering, and Ocean Acoustics in general, which both came at the perfect time and - looking back on it - could have made for a great professional life for me, personally. At that time, though, all the Physical Oceanography college training was focusing on water currents and waves, beach erosion, etc., of which I had little clue, nor interest. Indeed, I can still remember by those days having thought that submarine acoustic/sonar/quieting research must already have "been there and done (all) that". Perhaps that, too, was a deliberate secrecy from the public, to Keep a Step Ahead.
And (for another example) for many years I had known about Tullibee, who has really been savaged as ineffective, in the historical record (though her initial idea - to make a quieter reactor cooling system by exploiting coolant convection for circulation, eliminating noisy pumps - has to me always seemed brilliant). Don't know much of anything about Lipscomb - and maybe that was always the plan: to "drop hints" publically about Tullibee while shielding completely from view the "Real Juice", being squeezed out of Lipscomb...
In any case (in addition to having been born-and-raised just outside Philadelphia, myself) the early, "old-school" 688s, with their sail-mounted diving planes, are my clear favorites. I know all the later boats, ever since, now have bow-mounted/retractable planes: better for bumping up under- and through ice packs. But sailplanes - the further forward and higher-up on the sail, the better - really say "Cold War Attack Boat" like nothing else, to me. (No doubt memories from my youth, and devouring as many pics in books, magazines and on model box-tops as I could.)
Great little build and (especially) writeup, and submission to ModelFleet, Don!