Wonderful!
I've never really thought too much on this topic (and have never gotten into the comics), but your story to me makes a lot of sense regarding the difference in how they age.
Not a lot of women enjoy aging, but in Lois and Clark's case, I can see the situation becoming somewhat dire. I mean, really, can you imagine Clark looking pretty much as he did (when the show ended) and Lois continuing to age naturally up til now? It would definitely create a situation to address.
Then again, like you pointed out, that machine did give Jimmy some of Clark's 'life'...maybe, at some point down the line, that would help?
Loved this!
Laura