now, in lost switcheroo fashion, is it still possible that ben was doing the right thing? like, maybe the island has heaven-like laws, with which you can't enter via suicide?
That's quite possible, actually. Look at Michael. The island wouldn't let him kill himself.
or, was this finally the definitive "you are the bad guy!" moment?
I dunno. Mrs G and I were discussing the episode and I (in true comic book nerd fashion) drew the analogy (which made her roll her eyes) that, for all we know, the Widdemore-Ben conflict is basically what would happen if, say, Dr Doom and Lex Luthor were at war. At some points, you might want Doom on your side, at other points Lex. But, in the end, they're BOTH evil.