There is one for just the kids, which is disturbing on a few levels.

Why isn't there a mod that makes every NPC non-essential? (or, considering the forum rules, only the advlt essential NPCs?)

I can't find it at the moment on Nexus, but I could have sworn I saw it on there. I have the noessnpc.txt and undonoess.txt files, if you want them.
You just open the console in game, type 'bat noessnpc.txt' and it flags all the ones in the text file as 0 instead of 1

I've seen the list - I also saw someone claim it didn't work! Some NPCs would randomly still be essential.

I'll give that a try, make my own files.

That is true, some of them are still essential, there is apparently something else keeping them essential while others not.
Sadly, that's the best I can offer at the moment. When the CK comes out, I'm sure there will be a 'fixed' version up :]

There isn't an .ini setting for it this time?

tried it, all i get is syntax error blah blah missing parameter blah blah not saved blah blah. in any case it doesn't work. I used this:

http://www.gamefaqs.com/boards/615805-the-elder-scrolls-v-skyrim/61112816?page=2

http://www.gamesas.com/index.php?/topic/1282588-do-we-have-a-mod-for-killing-essential-npc-yet/page__view__findpost__p__19366658