To reduce traffic a little bit (e.g. in the last 12 hours or so there's been 191 hits for book titles from googlebot or bingbot), we could ask robots to not index any of wsexport.
User-agent: * Disallow: /
Would there be problems with this?
If we did this, we should also add rel="nofollow" to the gadget portal links on Wikisources (e.g. change this).