[MMM]

I think you actually have a pretty good itinerary. I agree with Godwine to give yourself at least a day in Yokohama.

Hiroshima is pretty far, and a half day in Himeji is probably enough. I would add a day in Nara and maybe a meal in Kobe.

Ask anyone from Osaka and Tokyo if the two cities are that different and the resounding answer is yes. I think the two cities have very different styles and personalities.

The guys that look like yakuza probably aren't and the true yakuza look like normal guys. I would take that off your list of things to do unless you want to lose that brand new camera of your.