This was our 3rd cruise (2nd Norwegian) so we are not as experienced as others on this site. Nonetheless, I'll share some thoughts.
1) One of the things we most enjoyed on our last NCL cruise was the great music on the pool deck every night. It was loud, fun, the cruise directors and many staff danced and got the crowd going - we stayed up every night till 1 or 2 am! The music around the pool was marginal during the day, and non-existent at night except in the Spice area. There was a huge, grainy video playing and lots of people dancing, but it was very crowded and the music was just loud, not fun. Never saw the cruise director.
2) LOVED the Howl at the Moon! Those 2 guys and a girl are great piano players, good singers - so talented! They improvised and laughed and THEY had a great time, so everyone else did, too. Best part of the trip, by far.
This is the last cabin on the starboard side by the handicap entrance to the Italian restaurant. It was quiet and although the kids area is on the same floor, we never heard a thing! The cabin itself is fine - except for the awful lighting throughout - but we didn't like the balcony. It has a solid bottom, so you couldn't sit and look out at the water or the port - you had to stand up. Our steward (Eduard) was great - always smiling, always pleasant and unobtrusive.