The Interactive Recommender can recommend games to buy. Some of those them may be things you already wishlisted (assuming you didn't filter them out). Are you suggesting adding the inverse option: i.e. only recommend things that are wishlisted?

Yes, but that's only half of it. The other half is something to clear out redundant entries in the wishlist: items that are in it for years or have negative reviews etc. Negative recommendations of sorts.