So what you're suggesting is that there is reckless play that represents a threat to the safety of the players, and that this reckless play could be prevented by the 'enforcers' of the league, but they choose not to prevent it because they do not want to take a 2 minute penalty. That about it?
No one is or ever will be afraid of enforcers, instigator rule or not, because there are too many players now who just aren't worried about their reputations. It is impossible to force someone to fight. All a dirty player has to do is turtle up. Refs break it up, dirty player laughs, goes about his business. Players and fans of other teams hate him, fans of his team love him.
Being right, being the 'good guy', does not make you tough, nor does being tough make you right. Players policing themselves just means that the toughest guy makes the rules. What if he's an *******? Getting rid of the instigator doesn't just mean that your enforcer can go after some cheap shot artist. It also means that the other teams enforcer can go after your star players. Do you really want some goon running up throwing haymakers at Nick or Pav or Hank in the hopes of injuring them, or at the very least getting them off the ice for 5 minutes?
Why would anybody do that?? That is just ridiculous to assume that removing the instigator will automatically have other teams tough guys chasing down Pavel. I see Ott and Ruutu doing that but I don't see guys like May and Boogard and Parros doing that. Just because they can do it if the instigator rule is gone doesn't mean they will.