If WHM is supposed to be the "burstiest dps" healer, then POM and Misery should be made better. Let Misery be DPS neutral at least and have POM reduce cost of offensive spells (if not all spells) will go a long way with WHM MP issues.

As for Assize, maybe a trait that makes it more powerful the longer you hold it in combat (up to a reasonable cap of course) rather than having 2 charges can still give it some flexibility while not enroaching sage's equivalent and as a plus fits more to WHM's bursty nature.