Kings isn't for the raiding, more so for 5-mans. It seems like that is the preferred buff in 5-mans. If tanks and dps don't require kings anymore for 5-mans, then it can go away.
Aura mastery doesn't really matter too much I think. Most of the time, the healers and caster dps are clumped right on top of each other or spread way to far out to get it. Also, the auras that holy pallys put up are really only for the caster groups, as the ret/prot pallies can cover each other.
I'll have to play with sanctified seals to see if it does increase crit.