Seconded. The "new releases of authors I've read books from" is one of the things that would give me the most value -- if it actually worked properly, which for me it doesn't, since it only seems to show _some_ random new books from _some_ of "my" authors. Sigh.
The recommendations basically crapped out on me after a few hundred books. It seems there are a few cliques (graph) of recommendations that are pretty independent and if you have read these cliques in a genre recommendations just suck.
But plz give me some query syntax like https://docs.microsoft.com/en-us/windows/win32/lwef/-search-... and most importantly the ability to filter out certain tags.