I agree with your views on Punisher, I'd put him at chaotic good. He doesn't give half a fuck about the fact that he's not allowed to kill people, but the good in him makes him respect what the authorities stand for and subsequently refuse to tangle with them. The good in him is the only reason he's a hero.
I'd have to take gambit508's side on Galactus, however. I think Galactus, being so far above most humans in intelligence, power and just plain size, can't spare any tears for the lesser beings he kills, especially considering he needs to do it.
Just like your neutral good ranger can't spare tears for the game he hunts. Just like you, washing your hands and killing trillions of germs in the process before you prepare food for the homeless. (I assume) If you do it because you have to, it's neutral. If you do it because the death rattle of billions of humans amuses you, it's evil.
It's not about what they do, it's about why they do it.