Great series need great writing. The West Wing is a fine example of outstanding writing. Plots are actually given some thought and the characters are written true to themselves. There are no instances of the characters failing to act or being forced onto certain paths because the writer's had decided that this would happen, regardless of the reality of the situation.
And this is the issue with OUAT. Characters in this show are not written well enough, their arcs are not given enough thought. The writers have decided on a course, but rather than think logically about that course, they've settled on the easiest way to get there, regardless of how badly it comes across. There is a world of difference between character development and character drama. Development feels natural, drama is not.
Take the evil Queen winning all the time. She does not win because she's smarter or more cunning than every other character, she wins because every other character is written to be stupid. Never has the words 'Evil wins because Good is dumb' ever been more apt.
The will they/won't they crap between Mary Margaret and James is another example of lazy writing. Writer's seem to think that a happy couple is difficult to write for or boring to those who watch the show, so they do anything to prevent that... Even to the point where I was ready to leap into the tv to kill the stupidity. It is possible to write an awesome couple without relying on UST or will they/won't they. It just needs some thought. In addition people become far more invested if either side of the great pairing is in danger.
I'm not even sold on the basic idea that Henry is Snow's Grandson. Unless this is explained in later series, how can the Queen or Rumpelstiltskin have left the town to adopt the kid, just so he can run off to find Emma later? It's a macguffin that doesn't make a lick of sense.
In addition why is this place so horrible? So they're stuck in small town Maine without their bestest buddies/lovers etc. But as nobody remembers anything. (with a couple of exceptions) why is it so bad? No seriously, why is the queen being the mayor of a small town considered some kind of victory for her?
Nor, for that matter is the writer's insistence on trying to give a sympathetic back story to the Queen as a reason to feel sorry for her. A. it was the worst mash of 'women are only evil because of the bad men' and 'she had her heart broken, that's why she's mean' that I've ever seen. Sorry but women can be evil, they can be selfish, we can be cruel without having a sob story in our history.
I still enjoyed the show, but it isn't a show that's going to stand the test of time. It's bubbly froth that could have been outstanding. And that's the worst thing about it. Please writers, stop mistaking soapy drama for character development.