All I think of is a Geralf stitched together force from Innistrad. I could see so many crazy shit for these guys.
Hell the lore could be hilariously dark, like harnessing the power of Sigmar's thunderbolts and storms has supercharged their flesh laboratories and they constantly need to keep up with the energy spikes, leading them out into the wider realms to seek bodies and rare resources and materials.
Factories full of machinery that intakes certain bodies and spits out new monstrosities.
Bonuses based on the sheer number of slain models.
The zombies are the villagers of the surrounding towns, working the machines of industry one would find in Chamon, the factories of fleshwork and the crazy laboratories where all the inventing happens.
The Abomination kit could be a bits wonderland that can make hundreds of different combinations.
It wouldn't even be that hard to make.
Zombies and Frankenbodies would be battleline, Werefleshers would be the fast cav unit, the abomination would be the monster for the release.
A special Leader version of the Werefleshers (The Wereflesher Alpha) and the Frankenbodies (Better Brain Frankenbody) to allow battalions themed around the unit types.
The only kits I would release would be:
Wereflesher (werewolves)/ Frankenbodies kit like the Crypt Horrors/ Crypt Flayers.
Zombies repackaged in boxes of 20
The Fleshpatch Abomination which is a behemoth model with a huge amount of bits to allow maximum customizability.
A blister of a Mad Doctor and his Ghoul henchmen or a Mad Doctor Riding a giant flesh monster to better observe his creations running amok.
Then just add a few battalions:
Wereflesher moonpack
FrankenGuard
Specimen Collection Force (Mix of both)
The Mad Doctor's Masterpieces (3 Abominations)
It could totally be an interesting faction for Death, and can easily be dark or humorous as need be. Don't want to hijack your idea user, but it sounds pretty clever.