Use Esperanto when no translation

Well, it seems closed now. I personally have no experience with Ido, so my opinion is not an very informed one. Thus said, I agree with the general consensus, that Esperanto make a better match for Ido fallback than English.

I had a look at the Wikipedia Ido article in Ido, and I find them rather transparent. Thus said, as far as I understand, the fork was mainly conducted by French locutors, and French is my native language, so I might be helped with some bias toward French traits. But maybe we could also set a fallback from Esperanto to Ido. I'm not sure that it is so much interesting, as Ido community is probably far smaller, so I would expect that the Ido version have far less content to fallback on. There is also the wikitrans stuff, that might be interesting to fallback in, that's an automated rule based (as opposed to statistic based) translation of the English articles. But it would require more thoughts on how to integrate such a fallback.

We could make the reverse fallback as well, but since even MediaWiki core is only 25 % translated into Ido such a fallback would mostly be symbolic.

What about the wikitrans translations then?

I'm not sure that wikitrans has to do with language fallback in MediaWiki. For automatic "translation" of page content, we have the LanguageConverter, which has nothing to do with language fallbacks of the interface.

WikiTrans is good as a Software-as-a-Service backend for ContentTranslation but it's use for fallbacking interface would be bit strange