That's most helpful, Peddrov -- many thanks. I'd thought of the issue of different brake pads fore & aft if I use a CSS rim on the front. Not a big deal, really--just a matter of extra spares. Might also just go with ZACs front & back, & your experience with those is very valuable too. My current bike, an Eclipse, has (now) ten-year-old 700c Alex rims, which have been completely trouble-free.
Still thinking about the Pitlock possibilities, as well as alternatives for keeping hubs & wheels attached to the bike...
Cheers,
J.