The first thing is the Seeker Chariots of Slaanesh. Comes with Aura of Acquiescence and Rending Claws, you have an Exalted Alluress on top that's WS5 with S3 I6 and 4 attacks. Alright, not that bad. The Seeker Chariot itself is AV11/11/10, Open-Top, Fast and comes with 2 HP. This doesn't sound too good at first, but I'd like to point out that it's immune to Poison and Bolters because of the AV11. Open-top is bad news, but if you're going to pen it, you're most likely going to kill it anyway.
However, that's not what you should be looking at. What you should be looking at is the Fleshshredder rule that comes with each one of these dudes. They're basically impact hits, or Hammer of Wrath in 40K. When you get smacked by one of these chariots, you're taking D6 S4 AP- Rending for each Hull Point it has remaining. That means the normal chariot puts out 2d6 S4 Rending auto-hits at I10 when it smacks you in the face, and the Exalted Chariot puts out 4d6 S4 Rending auto-hits. Statistically, you're looking at 14 hits on average from the Exalted Chariot and only 2.33 of those will be Rending 6s before the Alluress swings. That's not that great, but then again, the Exalted Chariot only costs 90 points in the Heavy slot.
The other little contraption that Slaanesh gets is the Hellflayer. It's basically the same thing as a chariot, but it gains Soulscent. For each unsaved wound you deal with the impact hits, the Alluress on top gains that many additional attacks. Not that bad, but not that great either. The only plus side is that the normal chariots (Heavy) can be taken in 1-3 for 40ppm, the Hellflayer from the FA slot at 60 and the Exalted Chariot in the Heavy slot for 90. Whenever I compare the cost of these dudes, I always look at the cost for 6x Fiends at 180 or 10x Seekers for 170. The Fiends put out 36 WS4 S5 I5 Rending attacks on the charge with Beast movement, the Seekers put out 50 WS4 S3 I6 Rending attacks with Cavalry movement. The only real difference is that with more attacks comes a greater variance of Rends, but S5 over S3 gives better reliability in terms of actual wounds dealt to MEQ. Oh, and I guess the fact that Seekers get pseudo grenades also help.
Another thing I look at is the imprint the model has on the battlefield, both in sheer size and accessibility and perceived threat. I would never take a normal chariot simply because you want to take 3 to get max mileage out of it. However, the size of these bases makes it a nightmare to place via DS and even a bigger nightmare to get them in combat. That's why I think the Exalted Chariot is the best one if you were to take one. It's the smallest out of them and has the best cost to damage ratio. If you look at the size of the model compared to the other two units I suggest (the Fiends and Seekers), you'll get the same size unit model wise, but it'll cost half the points and therefore, will put out half the damage. However, and this is big, the chariot is AV11 and therefore doesn't die nearly as fast as the other two and is half the points. The downside to this is that you're basically charging into melta range because you can never be stuck in combat as a chariot.
Lastly, we'll briefly cover the Screamers and Flamers because they got new rules. They both got better: Flamers are now 2W, 5++ instead of 1W, 4++. They lose their Bolt but got a decrease in points, so I think that's much better considering their main purpose: To light up MEQ like the 4th of July with Breath of Chaos. Screamers are now pretty ridiculous.. their Lamprey bite is S5 AP2 with Armorbane and each of them puts out 4 attacks on the charge with WS3 I4. Let's put it this way, 9 of them charging kills a 10-man MEQ squad on their own and do something like 17 pens to a Rhino. It looks like if you want anti-armor, Tz is the god to do it.
Depending on what my CSM army needs in the new book, I'll probably get myself some Daemon allies.
Did you guys know that I had a Khorne Daemons army for WHFB? At the start of 7th Ed, I went 8-0 (yes, I stopped at 8 on purpose) with the army and sold it immediately. I literally did nothing but push models forward on turn 1, charged on turn 2, and won on turn 3. As much as the 7th Ed. Daemons of Chaos army book is my favorite book to read, it was the single-most overpowered book I have ever seen, played or will probably ever see from Games Workshop. They're not nearly as bad in 8th Ed., but the horrors they inflicted in 7th Ed. will never be forgotten. And yes, it is written by Mat Ward, the same guy who wrote GKs and Necrons.