So do i have this straight here:
Rumpelstiltskin/Mr. Gold was a coward and about to lose his child to the war with the Ogres. Enter the Dark One Zoso whom wants to die so he tricks Rumpy into killing him, thus freeing himself and giving his curse/powers to Rumpy.
From what ive gathered so far that during this time till Baelfire was lost, there was no other magic in this realm. Well except Fairy magic.
Now once Baelfire was sucked into that portal, Rumpy had to find a way there. Now guessing his only way to do this was find a bean. Guessing some reason he couldnt find one and Mad Hatter couldnt find a way here either.
So he then came up with the curse but realized it would be better for someone else to open the curse. So he found Cora and gave her a book of magic, which besides Fairys means that she is the only one besides him that can handle magic.
But seeing how Cora wasnt on the right path for Rumpy or some reason wasnt following his desired plan, he used Regina to get rid of her and used the events in her life to get her to where she would unleash the curse.
Guessing at the same time he also gave powers to Maleficent for unknown reasons. Again maybe as a fall back plan.
Now once curse is hit and all transported to Storybrooke, Rumpy had to wait till timeing was right for Emma to finally come there.
Guessing he wrote the story book to get things started cause his whole plan was to get to our realm so he could go get his son, but still needs his power cause hey he is a coward.
So other words this was a plan from the start for Rumpy to gather power, and help from others to find a way here.