Pretty much what Ash said. Certainly I recognize there’s some artistic and creative value in any translation, but ultimately what we’re preserving is the films, not the translations. If one translation is clearly superior to another, then I use the superior one. If the preferred translation contains flaws, I feel no need to preserve those flaws, and will edit an official Lucasfilm-blessed translation without any regrets. Yes, there is absolutely some historical value lost–a goofy old translation with misspelled words and occasional bad translations can have some novelty and nostalgic appeal. But that’s not for this project.
There’s even the issue of the duelling roles of subtitles–is it to translate the English dialogue, or to transcribe the dubbed dialogue in another language? I always go with the former wherever the dub does not provide the most accurate translation (the translation choices for dubs can be governed by other factors such as matching lip movements, so they can sometimes be off).
Once we get to the point where it’s actually not clear one translation is better than the other, and it’s more of a matter of opinion or taste (and I’m still open to the possibility we’re already there with Japanese), then I’m more resistant to the change. There’s absolutely value in consistency between films (so if you change one translation, you should change all three to match), and in not introducing a new translation when the familiar one was just as good. Also, to be clear, the Japanese subtitles we have right now are based on the original home video dubs, but they’re already not a perfect match. Those Japanese subs contained Furigana, which I couldn’t find a way to reliably reproduce, so I asked one of our members to go through and re-translate those words as needed, or just remove the Furigana if it wasn’t needed. The newer translations don’t use Furigana at all, so they’d be more faithfully converted.
As for maintaining multiple versions, long ago I made some pretty hard-and-fast limits on what this project would support, to preserve my own sanity as well as those who try to sort through the project themselves. For example, I do not provide subtitle variations for the 1981, 1985, or 1993 variations of the films–just the theatrical versions. Multiple translations per language is another.