I think we’re all going to have to agree to disagree on this one. A lot of our assumptions are just that: Assumptions. It’s still way too early to try to guess where Rumpel’s character will go. We don’t know what happened to Baelfire, we don’t know what happened to his first wife, and we don’t know his reasoning behind making the Dark Curse. Judging by the interviews with Robert Carlyle, the writers and the producers, there’s a lot more story to tell with Rumpel and the Dark Curse. I think one of the producers even hinted that Rumpel didn’t create the Dark Curse for evil, but for something else.
Like Midnight Dreary stated, Rumpel could end up like Spike. Redeeming himself in the last minutes of the entire series.