Would it be possible to add the ability to whitelist or blacklist specific mobs? Or at least the ability to disable it for none hostel mobs?

Why?

I figured it would be easier than checking to see if the item the player is using can do damage above X because what if I'm trying to break grass and there is a mob there that I don't want to hit?

This is going to happen so rarely that I don't consider it to be a problem. Mod will hit the entity only when it is right under the crosshair