Sounds like a great cabin to me. Here's the link for the Sun's deck plan: http://www.uk.ncl.com/fleet/09/deckplans.htm#. The advantage to the cabins on deck 9 is that you're both above and below other passenger cabins, so it should be nice and quiet.
We were in cabin 0215 a couple of years ago -- up one deck on the other side of the ship and a little further forward, and it was a great location. Close to both the front stairs and the elevators going to the atrium, as well as the set of forward elevators.