I think that those who are pointing out that in traditional literature a woman is perceived as less valuable are correct. But remember, many of the characters you are referring to were written in a time when it was openly believed that a woman was less valuable than a man.
However, I don't think that is the case in L&C fanfic. Most of us did not grow up with the notion that men are more valuable than women...in fact, most of the people on these boards ARE women.
Also, I think it was Yvonne who made the point that for most of us (women) to explore Lois being left alone is a very hard thing to read, because it does hit too close to home with the idea of losing our husbands.
I'm not saying gender roles don't exist-they do, and in a way it is programed into us. There is a natural inclination for the male to be the "protector" (and as someone else said, Clark is the protector of the world, so that just enhances it.)
Also, just given the character's personalities Lois and Clark would both be devastated if the other died, but in very different ways. Just because of who he is he would naturally blame himself. In most situations, I can't see Lois blaming herself for Clark's death because she didn't protect him, but this is very likely scenario for Clark.
Just my $.02.
