I think that that depends on the circumstances. I think it may be a good idea for George to befriend Shiloh's Gryffindor friend, and then meet her, and slowly develop a crush on her, which could lead to love. I think that like you said, George may be attracted to the rebel type, because that would bean that she would be able to take a joke, or laugh at a prank. George would also like, I think, a strong person who cold think for herself, and like Ron, I think he would be a sucker for a pretty face.
Secondly, do you think that George would date or have a crush on a Slytherin?