Welp, I ended up going with the parkerized Springfield Mil-Spec for $620.
I weighed all the factors - price, features, upgrades, warranty service - and went with the Springfield primarily to have a strong frame and slide to start with, backed by Springfield service.
After lots of in-store handling, I find that I don't really care about a lot of the upgrades on some other guns, and even prefer the "unenhanced" versions in some cases (flat grip safety, non-ambi thumb safety, no front serrations). Some aspects (short vs long trigger, sights), the jury is still out on, so upgrading later would be fine if using the gun reveals a different preference. In the mil-spec's case, at least I get the tall, 3-dot sights cut with good, sharp lines.
I ALMOST went with the Armscor-made Cimarron, as I love its beautiful simplicity and close-to-Browning specs, but the forged frame and lowered/flared ejection port seemed too important to pass up on a gun I expect to keep forever. I would love to try one of those Cimarrons out at some point, though, just to compare.