Love the idea! My one suggestion would be to add the ability to filter out children's books from the results. After I added Hitchhiker's Guide, Children of Time, and the Iliad, the majority of my recommendations were children's books. Or, maybe the tool is telling me something...

Agreed I would like to somehow do that. At the moment it's a bit tricky as some books we might classify as for children are more broadly enjoyed (e.g. The Little Prince). One way, I suppose, would be to use a dozen very explicitly children's books as "anchors" and assume other books that intersect a lot with those anchors must therefore be children's books as well. Then I can create a filter. Shall investigate :)