I'm with the OP. I've been playing Skyrim since it came out. The grey-face bug was introduced into skyrim by an early update to the game and was never fixed, because of the CK workaround.
As for mods and load order, I have moved offending mods to the end of my load order, the very end, past all patches and DYNDOLOD, and still encountered it.
How much do modders and mod users have to jump through hoops before we can reasonably call this a bug and attempt to fix it?
The script sounds like something I would definitely try. It also sounds as if it would be compatible with any mod that adds NPCs.
I am currently using all of the Bijiin mods, Improved Bards, and The Ordinary Women.
I use MO2, so I can move them around and keep the load order as follows:
The Ordinary Women
I also use Interesting NPCs (3DNPC) and Cuyima's update to the faces.
At this point, no greyface.
The problem comes when I use Populated Skyrim Hell Edition for Open Cities with civil war.
If a script would keep me from having to choose which mod I like better, sort through mods' BSAs and patches, and delete NPCs baked into my saves with Resaver, I would be perfectly happy to simply play with my load order until everyone looks right.
FWIW, zEBD does something like this "on the fly," though it is not as customizeable as the regular EBD mod, which can change height, though I don't know if it changes weight.
Load order isn't a bug either, but BOSS and LOOT exist.