Only new units in the box are the Scriptor Mortis and crossbow ghosts. Fortunately for me though, the only existing models included in the box that I already have are the Spirit Torment and Chainghasts. Everything else will be all new to me. Considering my wife plays DoK, this box seems perfect for us.
I've been dreaming up what I'd like to see for Nighthaunt in 3rd edition. Reworked Ethereal to ignore negative modifiers when making save rolls of course so we still get access to Mystic Shield. But seeing Kruleboyz get Frightful Touch (Venom Encrusted Weapons) as an army wide battle trait makes me hope Frightful Touch moves from certain warscrolls to an army wide thing for us, but reworked. Nagash's new warscroll is also missing Frightful Touch, which makes me think it's getting a rework. I think it would be really interesting to see Nighthaunt lean more into bravery reduction or something similar to fit thematically with them being super spooky ghosties. It could maybe work kind of similar to Nurgle's Disease mechanic. An unmodified hit roll of 6 could give the target unit a fear point or something. And then the more fear a unit has, the worse they do during battleshock tests. I'm not a pro at AoS so I don't know if straight up reducing a unit's bravery by the number of fear points would be too good or not though. But I just want to see more thematic rules like Nurgle's disease over straight up mortal wounds like Kruleboyz. But like our army cares so much about bravery and enemy units failing battleshock that I think it would be sweet to lean even more into it.
A rework for Wave of Terror wouldn't hurt either. It seems like such an important thing that just never works out for us. I don't think making it too easy to get 10+ on a charge roll is the right way to do it, but I think a battle trait that mostly doesn't do much because it's hard to roll that high on charges needs some attention.