I have no idea how you would get 220 people on a 737-900. I flew them in India and they packed em tight. We could take 212. Boeing tried to sell it as a 757 replacement. While not a bad aircraft it certainly is not the machine the 75 was/is. Having said that, it is a very small step from -800 to -900. Add ten minutes to the turn and all will be well.
Jet
Jet