"And the Valar already know they can restore light to the world if I don't manage to head off whatever happens to the Trees."
"It seems like it might be inconvenient if you all die or something but I'm probably just a little too accustomed to 'and then a bunch of people die' as a possible next narrative item in arbitrary narrative."
"Well I think at least a few of my children are at some point going to marry. And no one in Valinor dies. And the Silmarils are sufficiently dangerous that having them in arbitrary hands might not be an improvement over them ceasing to function. Also, it gives any enemy with the capacity to kill my family the incentive not to."
"Good points all. Although if you have enough descendants it might stop being a good filtration criterion."