Some suggestions:
- Make one core formation per Chaos God. Might as well be specific! You can then tweak the sizes and soforth.
- I'm not 100% sure about the inclusion of the Daemonic Engines. These, I thought, were constructions made by the Chaos Marines or other Chaos forces and had daemons bound within, rather than being true Daemonic entities themselves. You're right to not have Defilers, for example, as these things are constructs.
- Soulgrinders DEFINATELY belong in the list, I'd make them a Core formation no less. Oh yeah! Indeed, the fluff is that the Soulgrinders in 40K are the least of the possible shapes these things could have. Soulgrinders are daemonic engines made from Defilers, so one would expect to see other daemonic "morphs" of the daemon engines. So remove the Lord of Battles and make your own, even more twisted, version of it. I would remove all of the Daemon Engines and make 4 large god-specific greater soulgrinders.
- The core Daemon formations could well do with Daemon Princes to lead them, or Heralds. Or both.
- I wouldn't keep the 0-1 limitation on Greater Daemons.
- As BL says, many of the names have changed. Daemonettes on steeds are now "Seekers of Slaanesh", Juggers are "Bloodcrushers", etc. Keep up man!
