I work on the Wikipedia Library program, and wanted to jump in with a passing thought I'd had about Wikisource and TWL. We'll be building search and discovery tools into the library card platform (
https://wikipedialibrary.wmflabs.org/) that's currently under ongoing development. They'll index all the usually-paywalled resources we have access to, but also open access content. As part of that process it's a desire of mine to index completed Wikisource works, though I haven't given it much thought beyond 'that would be nice'. This might be able to function as a kind of centralised search for all completed Wikisource works, if implemented.
If you're interested, the relevant Phab task is
https://phabricator.wikimedia.org/T169875, where your thoughts are very welcome. It won't be worked on for a while and I can't guarantee that it will definitely happen, but if it's something the Wikisource community would benefit from, then that would absolutely increase the likelihood we'll work on it.