2. Warhounds at 30 or 40 points, this is the same problem that GW has what are the right points for this type of army? We all know that the GW tweaks the points here and there, as a compromise for now lets throw in 35 points for a 3rd option, your list you choose, as only playtesting will tell. (For reference I still stand by 40 points.)
5. Wizards just to be themed I would have a Wizard in-between Chaos and Empire a Chaos Wizard in training if you like a Marauder Sorcerer;
Marauder Sorcerer +1 Atk Command:7 for 55 points
He would learn his extra command ability by raiding.
I would go for Spawn more in keeping and as you said they fought in battles.
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