I disagree on two fronts:
Rumpel did have magic pre-darkone, the cake appeared on his hand just cause he thought it. no other lost boy was able to do that.
and Emma is not the only product of true love, so in order to make her powerful Rumpelstiltskin had to add some magic to her parents somehow. they are both the purest of hearts and have pure and true love, so that IS powerful in itself, but it isn’t magic until a potion was made of it and bottled. so yeah, Gold did not MAKE Emma, but he did give her magic. because SHE could handle it without going dark. because he has power. love power that will protect her soul the way he wasn’t protected. while he was the savior, he went dark, but she doesn’t have to. he got a good replacement savior
you may be right about Pan though, the only place he was truly powerful was in never land. in story brooke he needed reginas vault and the cuff. I bet if Rumpel wouldn’t have the cuff he’d be able to kill him without dying