Before deciding how to "fix" the DOPS... I think you need to decide what the "goal" of the DOPS is, and specifically, how you balance between keeping players safe, and maintaining the "emotion" and "physicality" in the game.
Regardless of where you stand on that spectrum, players do need an understanding of what they can do, and what they can't do.
There is no rule, or precedent about punching/shoving a guy head first to the ice. To be honest, I'm not sure I've heard of an injury coming from this since Bertuzzi-Moore. Players have long understood that it is a "govern yourself" approach... in that you as a player have a responsibility to ensure that you do not injure another player, and that the primary determination of whether disciplinary action is warranted is to what extent a player is hurt.
Yes, Panarin got hurt, but apparently it's a lower body injury, which in reality, had nothing to do with the fact that he had his helmet off, and little to do with being tossed to the ice. Panarin got hurt because he tried to contain a pissed off player that is a heck of a lot bigger and stronger than him, and the league has decided that they're not going to punish guys for being too big.
In a situation like this, there are always calls to "suspend the act, not the outcome".... but it's not that simple. Take the flip-side example of Alex Edler - Zach Hyman -- and this coming from a Leafs fan. Edler is at the end of a 3-minute shift, going for a hit with a wide stance. His right knee goes out as he tries to turn to meet Hyman, who's changing direction. Hyman tries to get out of the way and gets caught in a bad way. Edler's "actions" are probably something that happen several times each and every night for every team in the league. Typically player takes their bump, game moves on. You'll suspend half the league trying to prevent that "act" from taking place.
Ultimately, with the emphasis on head injuries and concussions, I think a hybrid approach needs to be taken. The league (and I'm not sure a former fighter is the right guy to lead this charge, probably better to be a non-player who can set an objective criteria for what is acceptable) has to create an "exclusion zone" around players heads when it comes to extracurricular activities, especially in vulnerable positions.
You want to get in a wrestling match with a guy like Crosby did tonight? go for it. You want to both drop the gloves and fight? go for it.
Guy's hacking at your goalie trying to put a puck in? cross check him in the back. You want to punch him or cross-check him in the back of the head? you're gone.
Get tired of the wrestling match, let the refs blow it dead. You want to shove a guy's head towards the ice? you're gone.
You want to tie up a guy after a whistle? go for it. You pull off his helmet? you're gone. You want to throw a guy to the ice? you better make damn well sure that he's going knees or backside first, not head first.
Not everything needs to be handled by the DOPS after the fact. Why not make any head or face shots an instant game misconduct and stop using "roughing" as the appropriate penalty for it.