I'm really sensing a third evil power coming ... a TRUE evil power that is. Either a multi-season perma-baddie or a season by season villian would work ... but my gut says something worse and completely morally unambiguous in terms of being evil will be added.
In relation to that, I began to wonder about what they'll do with both Gold and Regina. Both are being kept very close to the precipice of achieving redemption but not so close that I'm even truly expecting them to actually go through with it. They could literally just keep them hanging near that ledge using Belle and Henry as permanent anchors to keep them from going TOO far (especially Regina since without Henry, she'd probably just murder half the town and subjugate the rest). Its also possible they let one or both achieve kind of a partial redemption ... i.e. they'll often fight on the side of "good" (or more, the side of Storybrooke itself) but will continually do very morally ambiguous things in the name of fighting for good (especially for Regina again ... she'll never become good ... just maybe 50% less of a bitch). I dunno, they have a LOT of options to choose from.