[Sombre]

Warhounds can be an auto spawn/summon allies troop of the more Marauder-esque leaders. You could also have them spawned by a Marauder scout of some kind and give them stealth - they'd be the only mundane chaos stealth troops then.

I think variety is good when it comes to chaos. If they have a large number of recruitables that's not a big problem - chaos are a pretty varied army thanks to the 4 different powers. As long as the graphics don't need to be hugely different it doesn't take that long to give Chosen extra fancy helmets, or glowing swords or banners or whatever, so why not have both types?