First impressions of GHB 2017 are pretty good for Death. FEC, Nighthaunt, and Soulblight all look a lot better. Deathlords and necromancers got cheaper.
Death: Red Fury got balanced. I always ran it on my ghoul king on terrorgheist, so it's not as good now, but it's much more useable on other generals. I like the new cloak of mist and shadows, but I usually ran that on my wight king, so that's gonna have to change. Ring of Immortality got fixed, so there's that.
Desert Legions:I'm still really salty about the fate of tomb kings, but there's a silver lining. Now that all of the named characters are generic characters, they can take the Death command traits and artefacts while having relatively unchanged warscrolls. Red Fury would be awesome on "Settra" and the Tomb blade no longer requires slain enemies to heal, just wound rolls of 6 and most characters have a lot of attacks, especially on the charge. Settra with supernatural horror could also be really good against the new horde meta.
Nighthaunt: I can finally start running my Black Coaches again, which have been shelved since GHB1. I also have a reason to start buying more spirit hosts and hexwraiths, which have a pretty nice new start collecting box. Deepstriking Mournguls is also awesome. It's too bad their allies aren't great. I think the only command trait is the reroll deepstrike. All of the rest of the traits are mediocre at best. The artefacts are mediocre also, especially since there are no nighthaunt warscroll battalions. I can't think of any reason Nighthatunt would take allies.
Soulblight: Battleline Vargheists AND Blood knights seems awesome, but on paper is different from on table. I like the Swift Death bloodline, but giving everything fly is lame as only the blood knights and maybe a vampire lord benefit from gaining fly.
FEC: I really like Feeding Frenzy. With a necromancer ally, 3 pile ins for ghouls. The demonic powers, er, I mean delusions are awesome. Royal Hunt and Feast Day seem especially good.The command traits are also good. I like Majestic Horror and Savage Beyond Reason, but I think Completely Delusional is the most powerful and fun. Their artefacts are ok, but can be really powerful in certain situations, mainly when paired with mortis engines or a summoned mourngul.