Works for me. The oldest technology is in fact the stargate itself, and that's simply because the seeder ships are launched with that kind of gate, which matches the parameter of the intended mission just fine. Everything else is a shell waiting for the time the Ancients were needed, and they'd bring a gateful of STUFF with them to properly outfit Destiny to finish their mission.
BTW, I'm also of the mind that while Destiny was the intended destination of the ninth chevron, this may not always have been so. It does seem a little wierd that EVERY gate in the universe has nine chevrons, and with the right symbol combination and enough power ANY gate can make it to... A smallish ship with an obscure mission that (probably) doesn't affect the entire universe all that much beyond scientific or philosphical curiosity. I believe that the ninth chevron may once have pointed to one or more other REALLY FAR destinations at some point, which has simply changed over the years.
My pet theory is that every gate was originally programmed to connect back to the Ori galaxy via the ninth chevron, in the event the two diverging civilizations made up one day. If that ever happened, everyone who had scattered around the universe would have the means to come to their starting point, no matter how much space or time had passed. Obviously this didn't happen, and at some intervening point the Ancients abandonned the concept. Instead, they hatched the idea of determining the meaning of LTUAE by sending a small ship WAY OUT THERE and simply modifying the destination in the base code of all existing gates (which we know to be possible from "Avenger" et. al.). The nine-chevron address has nothing to do with physical coordinate geometry, it's just a combination; thus anyone can gate THERE when the time was right.
While a theory only with little fact to base it on, this helps me personally rationalize why the Ancients would embed a single destination to EVERY single gate there is out there that happens to be a smallish ship in the middle of nowhere, with no apparent record in any surviving database about it.
Mark