Thanks!  I knew I wanted to turn that bit into canon, but then I had to stop and think about the mechanics of it.  What would happen if someone killed the primordial light-eater?  And the answer to that gave me an excuse to use the second bit, the part about the sorrowful Valar sticking a veil between Kor and Valinor.

Well, I figured since it's canon she barfs dark, why not Light also?  :-)