I think the best place for Belle to stay is with Mr. Gold, for both her own safety and because I think he feels like he wasn’t able to protect her in FTL land so he needs to be able to do that in SB to overcome his guilt as well. If he can’t hold it together with her, then Belle is strong woman and can figure out on her own where she should go, but she will need to be with someone who is powerful enough to keep her safe from Regina – either with Emma or the Blue Fairy. As long as Rumple loves Belle she will always be Regina’s target and will need to be with someone who has magic to protect her.