John Watson's choice of company: a sociopathic, former drug addict best friend who gets excited about murder; a lying, former assassin wife who shot said best friend in the chest; and a pot smoking, former exotic dancer landlady whose husband ran a drug cartel.
Benedict & Martin - because only best friends can tell who you are by your feet. That being said...it's a Hobbit interview, and the only feet ever discuss are Hobbit feet, therefore, if feet are the subject, then..Martin. Ben apparently thought it through.
Moriarty probably isn't back. I bet the whole ordeal at the end of S3E3 was either 1) Mycroft being sneaky to get Sherlock out of his exile or 2) someone using Moriarty as a way to scare the heck out of everyone