I'm just going to take a moment to put forward some information. I'm passionate about Chaos Space Marines and would love to see them get the same sort of support as we've seen other Codices get recently.
Here's the thing. With the exception of a few character models and maybe one or two entries, the following Codices are pretty much complete, with entire ranges of plastic.
Tyranids
Grey Knights
Necron
Dark Eldar
Space Marines
Blood Angels
Space Wolves
Dark Angels
Astra Militarum
These Codices you can pick up and have an entire force that is plastic without feeling like you're missing anything key. Yes, there are a few resin characters here and there, and one or two entries, like the Dark Eldar Beast Master and beasts and AM Ratlings and stuff like that, but those don't make up a considerable portion of the Codex.
These below have significant chunks that are not only old, but were haphazardly moved to resin:
Tau - specifically Kroot and Vespid
Eldar - ALL Aspect Warriors
Orks - a few vehicles and some other things, not 100% on these guys
Daemons - The Greater Daemons, a few Heralds, Fiends of Slaanesh, Beast of Nurgle, and a few others
and finally...
Chaos Marines:
-Mutilators - while new, are resin
-Obliterators - old metal converted to resin
-Khorne Berzerkers - from 3rd edition, some of the oldest plastic you can get
-Plague Marines - previously metal, now resin, a head shorter than regular marines
-Noise Marines - The Chaos Marine kit with resin tacked on
-Thousand Sons - The Chaos Marine kit with resin tacked on
-Chaos Cultists - Only way to get them is Dark Vengeance or little extra boxes taken from DV sprues
-All Named Characters
-Chaos Havocs - The only way to get Chaos heavy weapons is to get these old resin models
-Chaos Chosen - Don't exist. Yes, there are the DV models. Space Marines have Vanguard Vets AND Sternguard. Where are our Chosen?
Of special note, Chaos Terminators, Bikers, the Defiler, and of course the main Chaos Marine set are all showing their age, and all Chaos vehicles are still just Space Marines, but more expensive with that extra Chaos bits sprue tacked on. There are also some resin generic characters that, while beautiful, are starting to feel out of place..
The only things Chaos Marines have that are brand spankin' new are...
-Helbrute - Gorgeous, beautiful kit, easy to magnetize, a pleasure to paint and build, tons of beautiful options that cover all weapons it can have
-Chaos Raptors - Brilliantly stunning baroque style, ancient-looking jetpacks brought in, and Warptalon options for flavor. Also the best way to get Lightning Claws ever.
-Dark Vengeance - All incredible models, beautiful, fresh, with a new aesthetic that is far away from 'marines with spikey bits', a breath of fresh air in a whole army
-Maulerfiend/Forgefiend - Unique, new, and above all else, Chaotic, and I love it.
-Heldrake - A great kit that has lots of opportunity for conversion and paint, though I wish they didn't model it perpetually banking, but that's just me.
-Possessed - While not a new kit, is a great kit for bits and conversion, appropriately chaotic, and fits well with all the rest.
-Chaos Spawn - Again, not a new kit, but is fresh and a delight to work with, and has lots of opportunity for conversion.
-Daemon Prince - Our only true plastic HQ option, a brilliant model with lots of options and opportunity.
And with that I've covered the entire Chaos Marine range. Do I have to extrapolate?
The Chaos Marine range is a haphazard mess of old kits, resin, and fresh new kits that have a completely different aesthetic than the old. I welcome the new kits, but we need more of them.
Why am I posting this? To explain why I'm so frustrated. To me, it's less about the rules and more about the models. I started building Space Sharks and have never touched a Space Marine bike, Centurion, or Thunderfire Cannon because I just don't like those models. I would love to get back into Chaos Marines, but with the range looking the way it does, there's really no motivation, no impetus.
Yeah, you could make an army using only new kits. You'll have DV cultists, Forgefiends/Maulerfiends for heavy, Helbrutes for elite, Heldrakes and Raptors for fast, and the Chaos Lord from the DV set, with maybe a Warpsmith or Acolyte or the new Sorcerer or Daemon Prince thrown in. Does that sound like the type of army that typifies the World Eaters? The Emperor's Children? The Thousand Sons? Heck, even Black Legion wouldn't look like that!
The point is, HALF of our entries are resin, ancient, or both (with most entries being troop-based), and with the new Codex of Khorne rumored to be coming up soon, I'm terrified, TERRIFIED that Games Workshop is not going to update Khorne Berzerkers. If they do? Great! I will delete this post entirely, because it will be the first hint that from a model perspective, GW is finally ready to update the biggest bad that ever went bad in their verse.
If they don't? Then you won't hear the end of it from Chaos Marine players. To have a God-Specific Codex with no new models.. even if we DID get one for Nurgle and Tzeentch, unless those cult troops get updated, then in my mind there's no reason to invest in those lines for new players.
Here's hoping this new Codex is worth its salt, if it does indeed appear. It's going to take a monumental effort to make an almost exclusively-assault army perform the way it needs to perform.