I see where you're coming from, but leaving your feet isn't covered by a specific in game penalty. It's supposed to be suspensable 100% of the time simply because it's that dangerous. There are terms of engagement, an accepted right and wrong way to engage in contact, in every contact sport. Those baseline accepted rules exist for a reason. Sometimes accidents happen due to the speed of the game, like Halls case, but I don't think there are many scenarios worth the DOPS looking at where a player has a legitimate excuse for finishing a check while leaving his feet. If the intent isn't there on a simple accident you have a case for the DOPS not wasting their time even looking at it because there is no behavior to correct. You can land a huge check the right way where 99% of the time and you won't end a person's career in the process. In these cases, intent and injury should not be factored in. If it's a violation, it's a violation.
All hitting should not be removed and I don't like the shift towards a less physical game and these tightened rules meant to aid skilled players(BS slashing calls). This doesn't mean players shouldn't be held accountable if they violate the terms of engagement. Dangerous practice is dangerous practice, and while a huge guy like Getzlaf might get back up a player like Nico Hischier might not. I would rather see the offending player correct the dangerous behavior before they hurt someone.
To partially continue on the Marchand rant... If the DOPS even did a halfway decent job, Marchand wouldn't still be intentionally elbowing people in the head. How absolutely fvcked would this team be if that was Hall and not MoJo? And Marchand is still playing! It's unbelievable. They never get it right, which is why some players don't correct their behavior. There's no incentive. On the other hand, Wood probably got the message on leaving his feet.
Anyway, I hope you understand where I'm coming from.