We definitely enjoyed the Dutch Haus. It was like a home away from home, and fun in its own way. The hosts were very accommodating and even had wood planks for the kickstands ready when we got there. I enjoyed the very personal experience a B & B offers. And yes, it seemed as though there were a lot of fun roads around Montebello. Had to stay alert on those tight roads first thing in the morning!
As for the 919, I have not had an issue with the seat yet. On the trip we did 200-375 mile days, stopping every 120 miles for gas, and I was not in pain. I can see how it's not luxury motorcycle seating, but by no means as bad as a 120 mile stint on a Ninja 250 I used to own. I agree that it's the perfect bike for this kind of trip. I hardly had to change gears on the parkway because of the down low torque. It is relaxed enough not to fatigue you, but was able to be ridden sporty on the dragon.
I really like the 919. I've put 6300 miles on it thus far. As I've heard it said, it's a bike that can do it all but is a master of nothing. Many on the Wrist Twisters forum have their bikes close to and over 100,000 miles with no major maintenance. It's a rock solid commuter and an all around fun bike. You really can't go wrong if you're interested in one. Some mention an 'exhaust stink', but I have never noticed anything in 6000 miles of riding. I haven't ridden a Nighthawk 750, but I think it's safe to say that the 919 is a more sport oriented bike. It has more outright power and the riding position is much sportier. I park next to a Nighthawk 750 often, so naturally I compare the two.