Personally, I think the Library belongs more to the homepage than the Wiki. I would be inclined suggest a move in the opposite direction - pushing stuff from Flat Earth Literature into the Library.
In my head, the Wiki should be primarily for our own work, and based on our analytics, visitors seem to agree. Currently, the most popular pages are the FAQ (by an enormous margin!), followed by the Wiki's welcome page, The Conspiracy, Experimental Evidence, The Ice Wall. Flat Earth Literature is left far behind in terms of visits. Over the past year, the Library (even in its current less-than-ideal state) has been viewed 3 times as often as FE Lit, and people spent more time there on average.
That said, I'm not married to doing things that way. I agree wholeheartedly that merging the two is the way forward, and that moving it either way would be an improvement over the current situation. If there is a broad agreement that we'd rather have stuff in the Wiki, so be it.
If you'd be willing to consider a move in the other direction, I'm happy to help implement your ideas - a short paragraph per resource/section would certainly be helpful, and we can reorganise the resources to make them more accessible. I appreciate that it would come with a downside of changes coming through a bit slower, but my initial feeling is that we're unlikely to be changing the Library (in either format) particularly often.
Your question about where to upload stuff will be best answered by Parsifal (I'll prod him in a moment), but I believe we currently host our library resources on Amazon's S3 cloud storage service. It would be best if we kept things in one place for (at least) the sake of future-proofing.