Sacramentum, Therion, Necrophobic, Gorguts, Enslaved, Dismember, as well.
Agree, these are essential. As another poster mentioned, there's alot more A-list death metal than black metal.
I'd personally remove Nuclear Assault, Exodus, Monstrosity, Carnage, Nihilist, Belial, Napalm Death
Yeah non-metalheads wouldn't really need to hear these bands. Same with Malediction, Impaled Nazarene, Possessed... etc. Hessian-only material.
Manilla Road is an eccentricity, not a legend. CANDLEMASS is a heavy metal legend.
Also Power Metal:
*Hammers of Misfortune
These bands are all good, but I'd shorten the list to Iced Earth, Helloween, Fates Warning, Lost Horizon. maybe Blind Guardian.