Spoilers up through “The Return”
Here’s my theory: Baelfire is Jack from Jack and the Beanstalk.
There isn’t much to support this theory; mostly it just seems like it would be a fitting situation and the kind of storyline the writers would use.
Here are where I see the parallels:
I really like your theory. I wouldn’t be surprised if Bae’s name in our world turns out to be Jack both because it’s a common name and it alludes to him being like Jack and the Beanstalk. I wonder who his giant will be though. I wonder if it’s an actual giant or just a symbolic giant, and whether or not he’s actually killed the giant or not yet when we find out wherever he is.