There are some circumstantial aspects that might be relevant for Wikisource:

- With the emergence of machine learning, do volunteers really need to spend so much time formatting? Or will we able to use our data to train a system to do some pre-formatting for us?

- With the existing flood of data, can we consider ws as a relevancy setter? If a document has been transcribed/imported into wikisource, is that enough to make the document relevant?

- Considering that not all libraries might have the resources to develop their own platform, can Wikisource be used as a neutral platform by external agents as a complement to their own infrastructure?

Regarding the 15 years time frame, it might be a good exercise to examine different scenarios. Yes, one could be to think big, to expect growth and a favorable environment. But what about the opposite? What if there are *less* people able to contribute? 

Cheers,

Micru