Warbreaker - Vacher in the Cosmere?

Of the five scholars, Vacher is the one who was most able to change and shift his opinions and his actions around. I'm curious if it's always been that way though, or if his perception of himself has changed since the events of the many war after killing Shoshara. "I think that clearly Vacher's role in the Cosmere is highly important," says director Tom Tykwer. 'His claim to fame was as a master of the use of biochromatic breaths to awaken things'