Now with the curse broken and the option of returning home, I don’t see why they’d want to stay in our world. Also, it’s too hard to have 3 simultaneous plot-lines going. In the first part of S2, it was really dissatisfying to a lot of fans to keep track of SB present, EF flashbacks, and post- apocalyptic EF all at once.
Personally I do not see why they would want to leave Storybrooke… not everyone is for adventure … and I sure would not want to live in a pioneer / feudal society. I like modern medicine / machinery / and life style… and I am totally anti war.