Option 2 - if I could change any rule in hockey, it would be to the one that doesn't allow for penalty calls to be challenged. We have all seen the officiating get worse and worse in the recent years, and I think that allowing for penalties to be reviewed might be a good thing in order to keep the officials accountable. Also, this would make it so that there are more eyes on the play. One thing to consider is that this might slow down the game considerably, so that would have to be taken into account to make sure that the play isn't interrupted too much. Some sort of category or time limit might be a good idea in order to make sure that the flow continues, and people aren't sitting for 10-15 minutes waiting for the officials to make a judgment call, as this would make it akin to football which can be stop and start at times.