To be honest only the slaves of Nagash have any form of Undead monster... the naff-looking old gorilla Bone Giant, another relic from the 6th Edition era where they had less of an idea on what to do with Tomb Kings to separate them from Vampire Counts, also doesn't fit in an army truly loyal to Nehekhara. What is frail, ugly bone for a monster, when compared to glorious stonework carved under the orders of your King?
I still love my Carmen Miranda bone giant. That being said if we went full Tomb Kings fluff I agree with you.