I certainly don't think the Punk Zombies are broken, they are pretty squishy if not bolstered.
They are definitely my bread and butter model though, I love them so so much.
Haha
The Belles are great too because for 4 SS you get a (potentially) model with 8 Wd, 5 Df, Hard to Wound, and 8 Cb.
I see how it's possible to get a lot of damage from Crooked Men, but the mines they lay are usually just for deterring people, they don't usually get stepped on.
My luck with nurses is much the same, I don't want to spend 5 points on a model that doesn't do that much. For the same amount, I like to take Punk Zombies.
The Grave Spirit and Vultures are much like Sebs and Morty to me. It depends on who I am against. If I am against living or Undead things, I will take vultures because they can run in there and grab the counters for me but if I am facing something that does not or something with a lot of heavy hitters, I will take the Grave Spirit.
I like to start with one belle and tag the Spirit to her, now she is nearly impossible to kill.