I believe USFA is being careful and prudent in concentrating on developing their company, processes, equipment, and skilled craftsmanship to handle the steady growth that it has encountered. Don't get me wrong, I would love to see something in the world of USFA extras for us USFA fans. But I also remember how much fun Colt Commemeratives were when they began, but then went to absurdity with the astounding numbers of commemeratives that eventually dropped collector values in general.
That being said, I also believe that "Word of Mouth" advertising is of the highest quality and highest yield. A nice USFA hat or shirt would help spark up conversations. Especially with the sweet "US" logo. I wouldn't do mugs though, I have a plastic bin full of Fire Department mugs collecting dust.
Also, USFA already does Historical letters.