[Autumn]

The sister skill to Shine Knighting is Death Knighting, Shine Knighting is defined by it's defensive qualities, and Death Knighting is defined by it's offensive qualities.

Death Knighting, however, has a downside to using it that most don't tend to pay attention to, and that is the possession tag it marks you with upon transforming. Shine Knighting doesn't have any such downside to it, you are getting Light and Dark immunity for no downside at all, two components that are uncounterable to those specific archetypes, as not even Nihilist will stop immunities. (And at this point I'm almost not against proposing that it would.)

But yes, Shine Knighting should have a downside of some kind if its going to retain Dark and Light immunity at all, otherwise just making them hefty resistances like 25-30% is good too.