ooooooh what a nice question!! Okay, these are my personal headcanons:
Peter would love the Gracious, the one who would love to help others and give what they didn’t need to those less fortunate. They would support Peter in his kingly duties and help him with the harder decisions. They would be the one to ease his mind when the country’s troubles tried him to staying in his office late into the night. They would be the new perspective he needed to encourage him to take risks that would better the kingdom. They would make him a better king. They would be the bright smile needed to lift his spirits and make his day a great one. They would bring out his good side and keep it there.
Susan would love the Clever. Susan always tried to surround herself with people who challenged her intellect, like her siblings did. The Clever would give her that challenge and inspire her to be better. They would love her as she is, not focusing on her looks and rather her intellect and personality (though the looks were a perk of course). Susan would appreciate this, as many people who told her that they loved her only loved her appearance. When the accident happened, they would love her, and hold her, and keep her on the ground and focused in healing.
Edmund would love the Enduring, those who could handle how wrecked he was from his past mistakes and could understand how he had to act a certain way and keep up certain appearances to make sure everyone knew that he would never made those mistakes again. They would laugh with him and hold his hand when he was having a rough night. They would be able to keep him steady, keep him happy, and keep him whole.
Lucy would love the True. Lucy rarely tolerated the dishonest or faux. The True would be just that- true. They would encourage her to be good and better, helping others. They would live together in faith in Aslan and in others. They could mutually support each other through kindness, and reciprocate that chemistry onto the kingdom. They would embody ‘kill them with kindness’. The True would never leave her, never let her feel lost or unsure.
Love this!