FIX PLAYER FATIGUE!!!

For starters there is and has been an issue with line changes that goes back to at minimum last year and maybe longer. Sometimes your team won't change unless you switch to a new line other than what you originally selected and that usually fixes it but sometimes you are at the mercy of poor programming. Outside of that - players in the NHL are considered to be have been on the ice too long if they have been out there for over a minute and extremely fatigued for anything over 1:30 seconds. In a real life NHL game the most elite forwards will at best log 15-17 minutes of ice time per game throughout the year which is roughly 25% of the game. In means they hit the ice for a minute, hop off for 3 minutes and hop back on. 

Take a look at the NHL games and when they show players sitting on the bench after a pretty normal 45 second shift, they are absolutely tired. They will never be back to 100% energy until after the 1st and maybe 2nd intermission depending on their conditioning. Now it would be impossible to duplicate the stamina drain in a video game because most people don't want to sit through a full 60+ minute game each time but they are actually doing a great job making sure you have to use your lines wisely. It's not fun nor realistic if you can use only your first two lines for 80% of the game.