All of the sororities at Ole Miss are great. There are already elections that have occurred that show that every house has it's stregnths. She could be happy in any house...lots of them have girls from all over.
Please encourage her to keep an open mind...she will be happy wherever she ends up. It is a wonderful system with great houses. What is perceived as the house everyone wants on day one does not always end up that way on pref.Just go with her heart!