Honestly reducing the number of people that can be involved in ties would be a good thing as it would encourage a larger number of smaller klans that are actively competing for supremacy or it would encourage intra-klan backstabbing which is also quite enjoyable.

Currently there is too much potential risk (being kicked out of your domination klan) to overwhelm the potential benefits of stabbing your teammates in the back for a few extra medals. Unless you change the number of people who can be involved in ties you will continue to see behavior where one klan will share medals rather than engage in cutthroat play.