Did some testing and found that when I arrange the relationships on a bi-directional relationship, you cannot have a specific sort order on both sides of the relationship.
In my use case, I have an attorney related to a practice area. I want a specific order on the practice area page and then another order of relationships when viewing the attorney biography.
It might be good to add to_order and from_order database column so that you can arrange relationships independently of each other. You could keep the default order to be ID unless filtered to use the from_order or to_order column.