The NHL needs less fighting and more space (bigger ice).
Probably an unpopular opinion. But living in Germany and therefore watching lots of German hockey on a bigger surface, as well as lots of NHL hockey, I think the NHL could profit from a bigger playing surface (once all the players are used to it). The game does get a little bit less physical but much more creative with great passing plays. Comparing the DEL/European hockey with the NHL/NA hockey, it is really obvious that about 70% of NHL goals are really greasy rather than nice plays, whereas in the DEL you see a lot more nice passing plays and great goals. With the higher level of play and talented playmakers like Crosby, Malkin, Getzlaf, Kopitar, etc., I could really see that being a great change!