All I can say is maybe put the glass higher. I don't see how they could put a net above a hockey ring w/o it being in the way of fans.
I think this is certainly something the NHL should try to prevent, but they are not responsible for the death. It was a fluke accident. The girl was more likely to be murdered (something you have a 1 in 20,000 chance of happening to you) than killed by a bad slapshot, it just happened to occur to her.
There have been lawsuits filed in regards to injuries suffered in baseball games from foul balls, broken bats, etc. flying into the stands...basically if it happens accidentally, there's no liability unless the plaintiff can prove that the bat or ball was a defective product. Basically, when you buy a ticket to these events, you assume the risk of injury.
Aside from higher glass and netting...the only thing I could think of to reduce the risk of harm would be to change the composition of the puck from solid rubber to like nerf or something, or providing helmets for everyone! However, those last two aren't exactly good or feasable ideas. So depending on the cost, I'd say the only reasonable extra precaution to take would be to look into hiring Wonder Woman for some invisible netting.
"Hitler had pieces of flair that he made the Jews wear."
The girl died of a rare condition caused by her head snapping back on impact. It was and is a terrible tragedy. Sadly - The NHL will debate this but won't do anything to change it - the glass is already high enough without having to add a 2nd pane - netting at the end is feasible but unlikely.
Stylin' and Profilin' - Custom Made from Head to Toe.....courtesy of Michael's of Kansas City
I think it was Michigan/Michigan State that played in front of over 80,000 outdoors a year or two ago. What may be even cooler than the actual game will be the legends game of old-school Oilers (lead by Gretzky)