Not really, the main thing they could change is the order in which errors are checked when there are multiple errors, but even a lot of that is not likely to ch

Not really, the main thing they could change is the order in which errors are checked when there are multiple errors, but even a lot of that is not likely to change, eg html based stuff comes first. There are actual reasons for a lot of the subtleties, plus they have to have a stable contract for all the success cases as people rely on it. And its not hard to update, I have 800 or so tests against AWS that run in a few minutes.