Then there is the "Clue" that Moriarty gives about Janus Cars in The Great Game. I've always wondered why Moriarty would push the point home of the company's name, it's clearly obvious to anyone with a basic understanding of Ancient Roman mythology that Janus is the two faced god of beginnings and endings. Why would helping Sherlock with that be of importance?
As I've stated many years ago I think this clue is about something else altogether. Now we have Euros/Eures we could have the "It's never twins" twin of Sherlock giving us two faces, a beginning and an end, the concept of past and future, time, transitions and gateways matched by hallucinations, the Hawksmoor hint and the entirety of I.O.U.
Throw in Redbeard and away we go (Perhaps).
Good to start getting things possibly being resolved finally, or at least temporarily in my head resolved, for now.
-m0r