Hi Sandra/Spinster!
I support your request in the Wishlist Survey https://meta.wikimedia.org/wiki/2016_Community_Wishlist_Survey/Categories/Pr....
However, it's 87th in the list and no ticket assigned yet, so I don't know how long it'd take to implement.
I proposed a simple property Category and/or “Useful for / interesting to” to allow tracking ot items by projects, but it was rejected: https://www.wikidata.org/wiki/Wikidata:Property_proposal/Archive/30#category. Should we reopen this discussion?