I don't think Ethan needed super strength to lift Charlie like that. Charlie is a skinny boy, Ethan would just need to be in good shape. And he probably was, considering where he lives.
As for why eye-patch guy didn't shoot the other ones, maybe he thought that he'd get shot himself after hitting one of them. When you're 1 person and you've just shot a guy, and two people run out of the jungle, that's a dangerous and unpredictable situation.
The part I'm confused about is this upcoming bit with Locke's dad. Oh and yes, Sun's husband is Jin.