Hi!
I am happy to announce a new tool [1], written by Serge Stratan, which allows you to browse the taxonomy (subclass of & instance of relations) between Wikidata's most important class items. For example, here is the Wikidata taxonomy for Pizza (discussed recently on this list):
Very nice! One specially interesting to me is cycle detection - I just discovered there are many (as in, hundreds) cycles in various important properties such as P131 which break a lot of queries, and was wondering what could be done to expose/eliminate those better.