I think that sounds great! Ivy is too carefree and reckless as of right now to really be a leader of any sort, but she is super loyal (or will be) and they could make good friends or whatever. I don't have much of a plan for Ivy at the moment, but Samantha's plot could help her develop. She would definitely be up for stopping other humans from being changed, though, and this would help her accept her fate as a fairy at least a little. Besides, we need a place for the fairies here! :D