At first thought, it works for me.
But, I do reserve the right to sort of think about it a little further. The magnitude of the penalty is increased simply because of field position. Granted, a penalty is a penalty. But depending on where you are on the field, the magnitude of the 'sentence' is amplified.
I mean, I can't help but to think of the French dude who only stole the bread to feed his family.
My rule change is this. If you initiate touching a guy once he's crossed out of the big wide white stripe on the sideline, you are ejected and ineligible just like targeting. Otherwise, you're free to make contact and the ball handler should be prepared for it. Or I dunno, you can still call late hits if you want, but maybe make it a 5 or 10 yard. Just to try to make it a more binary call. I really haven't thought it through.
Also, I really don't know enough about the nuts and bolts of actually playing football to know about the unintended consequences of my idea. I just hate the meandering subjectivity in football.
I can stomach it a bit better in basketball. I mean, if you know how they're tending to call things, you can adapt. Baseball....same way. If the ump is giving you phantom corners, both batter and pitcher know. Football, one singular (except holding calls/no calls) call can really result in a game changer.