I don’ think Rumple wanted Ella’s baby to give to Belle, because I think the Cinderella story is what got Rumple in prison and in the state he was in during the Pilot and second episode. So…Cinderella probably happened post belle. But I’m really curious about why he’s trying to get all these fairy wands…on “The Shepard” episode he’s seen making a deal with the King in order to obtain yet another fairy wand.
As for why he’s wanting babies. I agree that he probably won’t hurt a baby..maybe he was lonely after Belle left.