That said, I think Baelfire is more important to the overall plot while the love story with Belle is incidental. It seeems pretty certain that Rumpel created The Curse in response to Bael's wish that he find a way to give up the Dark One's power.
Obviously we know that Rumple is going to agree to Bae trying to find a way to rid him of his powers, but I don't think that excludes Belle being part of the reason for the curse as well. This is my (current) theory as to how it all fits together, where both Belle and Bae play a vital role in the overall plot...
Bae wants Rumple to be rid of his powers, so Rumple agrees to humour the kid and let him try, even though he doesn't hold out any real hope of there being any way around it. But still, Rumple promises that whatever it takes, they'll find a way.
In the process of that search for a cure, something happens that results in Rumple losing Bae, (right now I'm thinking maybe Blue Fairy sends him to Neverland to protect him from his father, and he's there to this day until they can show us Bae as Peter Pan once they get the rights). This makes Rumple realise that if he's gonna find a way out of his Dark Curse and keep his promise to Bae, he'll first need to embrace his powers so he can become UBER powerful so he'll be powerful enough to cast a spell that will obliterate his Dark Curse.
So he goes about his business for a century or so, doing his deals and gaining his power, but not necessarily with a clear plan in mind yet for how to break his Dark One curse. During the last decade or so, this Evil Queen comes on the scene and becomes his greatest rival.
Then one day, this pretty girl named Belle comes along, and she kisses him, and it starts to strip him of his powers, but then she starts excitedly blabbing about the lady who told her it'd work. Instantly it flares up his anger because this situation is obviously the Evil Queen using Belle to rid him of his power so she can get the upper hand. The fact that if he'd just let it happen, he would have kept the promise he'd made to Bae, that doesn't even enter his mind in that moment.
But later, after he's kicked Belle out and he's had some time to collect his thoughts, he realises the error of his ways. Then for a split second, Regina gives him a spark of hope when he thinks maybe he can get Belle, and thus his chance at redemption back (the moment where he asks if Belle needs a home because her father kicked her out fucking breaks my heart every damn time
). But in the next breath, Regina says that Belle is dead, so there goes his hope of redeeming himself, both with Belle and for Bae.
This is the catalyst for him cooking up the "curse to end all curses". Both Bae and Belle believed there was still good in him. He made a promise to Bae to get it back, but it wasn't until Belle that he believed it was truly possible.
The problem now is that though he knows that love can break the Dark One curse, the love he shared with both Belle and Bae is gone, so that doesn't do him much good. So he's gotta use someone else's love to create the curse, (Snow and Charming's), then rope someone else's love in to enact the curse, (Regina and her father).
Personally, I see things playing out like this:
Episode 19 will show us in flashbacks how Baelfire became a tree in order to be preserved.
Episode 20 will show us in flashbacks how that tree became Pinnochio and how he was saved from the curse by being from the same tree.
This way casual viewers can see each storyline separately and it gives a shared storyline to Gepetto and Rumple- about the lengths a parent will go to save their child.
If they wanna go the route of having him be both characters, that's an explanation I could buy.