Pros
Great people. I've worked in the sports/entertainment industry for almost 7 years. Hockey people (employees & players) seem to be the most down to earth, easy to work with across the board. Fun environment and great events. Plenty of good benefits, perks, and employee moral building events. Pay is decent when compared to similar jobs in sports (not to be confused or compared with similar jobs in the non-sports world). Plenty of opportunity for advancement. both within the league office or to one of the member clubs.
Cons
If living and working in NYC isn't your thing, this would be a con. League office positions require much more travel compared to similar jobs at the team level (but this could also be a positive depending on your preference). All in all, nothing to major in the way of cons.