It was a season finale, not a series finale. They set up the second season with all those loose ends you mentioned.
So what now? Rumpel is a force to be reckoned with. I believe the way he betrayed Emma was just a glimpse of things to come. Regina might not be the villain of the second season at all.
The thing is it doesn’t feel like a cliff hanger usually feels to me. Most of the original things about this show were basically resolved they just Created a bunch of new ones all over again! What’s Henry’s role now? Or Emma’s for that matter? What’s the point of the book now? They really. Just blew this thing up lol