Maybe you could emphasize in the background color how their relationship brings the two worlds together. Like they're crossing over to each other's territory, and now the legend of the spirit warriors and the 'cold ones' has come full circle. Now the Cullen's are like honorary members of Jacob's tribe.
Though the solid white kind of does that. Like the past is the past and they're beginning anew. Their relationship kicks off a new era of learning to be tolerant.