In which we move along to the elites section.
Pros: ...they might get Feel No Pain? They have a 5+ invulnerable for all the good it might do them.
Cons: Khorne Berserkers are cheaper, have a higher WS, Furious Charge, and even pistols.
Overall, they're too random and people do the job better than them.
Pros: Options, options, options. One heavy/special choice, and four from melee weapons or special weapons. They also infiltrate.
Cons: Can't score? Infiltration is only of limited use sometimes. Massed melee weapon options require a Land Raider for effective delivery, so it's likely only Sarge will take an upgrade if anyone does.
Overall? I think they've a place sometimes for the sheer number of special weapons they can bring. 4-5 meltagun shots = dead armor, generally speaking. Similarly, 4-5 flamers = dead stuff, and I suppose 4-5 plasma guns would be comical as well.
Pros: Again, lots of options. Durable, and can deep-strike. They are passable at shooting and melee alike; twin-linked bolters + relentless for the guns and a fistful of power weapons for the hand-to-hand.
Cons: delivery system. Bringing these means committing to either personal or Chaos icons in your squads, which does cost points. Additionally, the Land Raider isn't that hot for delivery purposes since it's schizophrenic. Also, they're not fearless and they're 30 a head before options.
Overall? I see them being useful as mobile reserves in smaller, cheaper squads. Right now it's on the drawing board to have 4 guys with a chainfist, heavy flamer, and combi-weapon love with perhaps Lightning Claws in there. You really can't ignore that, and chances are they can do SOMETHING the turn they deep-strike in. They get a nice alpha-strike with the combis, then go menace things that don't have power weapons.
Pros: can be nasty in melee, or bring a mobile multi-melta. Walkers that hit at S10 and ignore armor saves are abjectly nasty in melee combat if they can get there.
Cons: Rolls on the 'crazed' table every turn. 1/3 chance of doing something stupid, but there are ways to mitigate that. Basically, you need to put it near something that its weapons won't hurt. IE: bring two close combat arms. Oh, no, you shot a Rhino in the side with small arms. Similarly, a missile launcher with frag shots won't hurt much either. Or, you just deploy the thing where it won't have shots at the other guy.
Overall? I'm not exactly sold on this guy. Crazed is what kills it for me; he costs about the same as a loyalist dreadnought and has a huge drawback, comparatively. (130 for Multi-melta, heavy flamer and extra armor for a loyalist. 120 for the same loadout and 'crazed.')
On Elites as a Whole
I think Chaos has two elites options: Chosen and Terminators. They're both special weapon delivery systems; one functions in a rhino and the other comes in off the deep-strike.
To be honest, Chaos made out like bandits in terms of Troops choices with a whopping 5 (six, if you count Summoned Lesser Daemons).
Chaos Space Marines
Pros: Versatile; they can shoot well enough and have 2 attacks each thanks to the pistol/ccw. They've got options in terms of bringing a heavy and special weapon at 10 guys, or 2 specials with ten guys. Also, they can be flavored with the various Marks of Chaos.
Cons: Not fearless. They die to sweeping advances, unlike their Loyalist brethren.
Overall: I think they're best used in 10-man squads in Rhinos with a powerfist and pair of special weapons, with perhaps a mark of Khorne (to win those close combats) or Chaos Glory (to pass those morale checks). Otherwise, use them as objective-sitters since they're at least cheap for it.
Pros: T5. Feel no Pain. Defensive Grenades. They were virtually MADE to pile out, rapid-fire, and recieve the charge.
Cons: Price, to an extent (23pts a head). They swing at I3, rather than I4. Additionally, they can only take special weapons; no heavy weapons for these guys.
Overall: I like them. There are other places to get heavy weapons in the chaos codex, and to be honest if you're wanting range then you take a smaller squad with plasma guns and no champ to claim objectives. I think they're best used with a powerfist, a couple of special weapons, and perhaps a Rhino.
Pros: I5. With gun upgrades, they can move and shoot and put out a hearty helping of anti-infantry shooting. Sonic Blasters grant either 2 bolter shots out to 24", or 3 when standing still. Doom Sirens are nasty heavy flamer stand-ins, and the Blastmaster is sick at range.
Cons: One-dimensional. Noise Marines are only suitable for hunting infantry; the Blastmaster can theoretically damage tanks but it's a single S8 shot and comes from a 40pt weapon.
Overall: Noise Marines require melee support; they can't take Dreadnoughts or Monstrous Creatures. What they can do is shoot unmounted infantry, but lots of people are MECHANIZED these days, which means less shooting. I think a smaller squad of 5-6 with Sonic Blasters might make a decent objective-camping unit that can contribute, but I'm a bit 'eh' on these guys.
Pros: NASTY in close combat; each guy cranks out four WS5, S5, I5 attacks on the charge. In numbers, they will annihilate most enemy infantry.
Cons: Delivering them to melee is the hard part. Land Raiders are not that great for the job, and Rhinos don't give you the charge. Luckily, unlike Orks the Berserkers still can give a good accounting of themselves when recieving the charge unless it's from an uber-hoss melee squad (IE: Nob Bikers, Seer Council, Space Marine Biker Command Squad of Doom).
Overall? I don't think the Chaos codex is set up to really get the most out of Berserkers, since there's not a good way to get them into assault.
Pros: AP3 bolters, slow and purposeful, and sarge has a force weapon. 4+ invulnerable save doesn't hurt, either.
Cons: Only good at killing infantry, and aren't even necessarily the greatest at that. The PRICE is another big failing point. 60pts for the Aspiring Sorcerer, plus 10-25 points for his psychic power. 25 gets you anti-tank, but you're basically buying an HQ choice every time you get a squad. 23 a head for the basic guys isn't too cheap, either.
Overall: I really want to like these guys. A 4+ invulnerable is cool, but only makes them adept at slowing down really nasty melee units, or surviving AP3 fire out in the open. The price of the aspiring sorceror really tanks it for me, as a minimal unit of 4 + sorceror runs 162, and that's with Doombolt as your psychic power.
Closing Thoughts on Troops
While they've got choices, some of the choices aren't that great. Khorne Berserkers can't be effectively delivered into melee, and Thousand Sons are just damned pricy for what they're really useful for. Noise Marines aren't bad, but are a bit mono-tasked, but I think you might be able to build around that. Plague Marines are a bit of a no-brainer, and regular marines can be kitted out in a few different ways to make them useful.
However, I do think Chaos can get away with 3-4 solid troop selections in an 1850-2000pt game.