Other than tournaments, I've been playing Chaos Space Marines almost exclusively these days because the army is a hoot. I have noticed that I never really make use of the elites section of the book. It has nine choice, but really, there's only five because the cult units should only ever be taken as troops, and I loves me some Noise Marines.
The reason the elites section is so neglected is because it is filled to the brim with things that make you go hmmm... Chosen are quite expensive, and die like marines. If you kit them out for assault, they won't get there, and if you give them four special weapons, you should have taken Havocs, you clown! I guess you could take Abaddon to make them scoring expensive Havocs, but let's be reasonable fellows about this.
Chaos Derdnots can't be configured in either of the loyalist builds that make sense. That is, the dual-autocannon build or the drop pod, heavy flamer, multi-melta build. I suppose a rocket launcher and autocannon build is acceptable, but nothing to go out and blow fifty American rubles on. Plus there's like, no kit for them and stuff.
Then you has Possessed, which are so straight awful you practically have to give them away on Ebay.
And of course, there are Mutilators. I think if you took a unit of one with either the Mark of Khorne or Nurgle, you'd have yourself a dangerous unit that your opponent will feel silly having to waste firepower on, but have to waste firepower in it nonetheless because he's got a pair of chainfists or lightning claws or sacks full of doorknobs that you don't want hitting you. Four or five attacks from the likes of those on the charge is unpleasant. But, they can't perform a sweeping advance, so they aren't so great for slaying infantry. So basically, you're hoping to deep strike your Mutilator safely out of sight, run around the corner next turn and yell "Surprise Clown Sauce!" and blow up a vehicle before he gets all killed. Of course, if your opponent is smart enough to avoid drooling all over the tabletop, they'll just drive their vehicles away from your Mutilator, who is slow and purposeful, leaving him with nothing to do but get all killed. So, you have bring three now to maybe get to use one, and instead of having a cheap squad that sucks, you have an expensive squad that sucks.
Already you have insight into my thought process when I design units.
Finally, there are Chaos Terminators. These may have promise. I begin by comparing them to their loyalist counterparts. The advantage Chaos Space Marines wearing suits of Tactical Dreadnought Armour have over Vanilla dudes is that they are cheap and flexible. The disadvantage is no access to storm shields, and they might run unless babysat by a Chaos Lord. Then, there are the Deathwing, which are kind of flexible, but expensive as hell. At least they can be made to score. I think they kind of still suck on balance.
So, if you want to run Chaos Terminators, you should probably do so in a way that takes advantage of their upside. Keep them cheap, and give them a job to do.
Now, because Terminators can't perform sweeping advances, they're not the best choice as an assault unit against infantry. If you try to build them like loyalist Marines by giving them power fists, suddenly your squad costs only five points less than the loyalist one does because you're paying 33 points for a stupid Champion who is exactly the same as every other dude in the unit, but has to pay extra for his weapons. You don't even have Storm Bolters for your trouble. It angries up the blood.
Then, if you wanted to give them the Mark of Tzeentch for a 4++, you're going to come out costing way more than a comparable unit of Assault Terminators, and will still get your butts kicked by them, nor will you have ATSKNF.
So, power fists are a bad idea, and they're not great against infantry. What was good about these guys again? Oh, flexible and cheap, right. Let's make them a cheap anti-mech unit. Three dudes, three combi-meltas, three power mauls. 112 points. Now it's a deep striking suicide squad that will hopefully slag a tank, and draw fire away from more important stuff as it advances. That's how I'd run 'em.
Another build that might work is to take four with power axes, the Mark of Nurgle, one chainfist, and either Typhus or a Chaos Lord in a Land Raider. They'll probably reach the enemy lines, and take more firepower than your average terminator to deal with once they're there. That's going to be a third of your army, however. It might work, but I bet it doesn't.
One final way to do it that might work, is to take around ten with five power mauls and five power axes, the Mark of Nurgle, and take Huron as your warlord to infiltrate them. It's 384 points that will be on the enemy turn two and cause a lot of trouble once there. Maybe toss in some combi-plasmas.
Anybody else got any bright ideas?
(Note: Dumb ideas will be dismissed with and explosive snort.)