Nerfs
- New dice modifiers rules. Not only +1/-1 (we had a lot of stuff that could stack +1 to hit/save) but there's no more minimum of 1 on dice roll, so bastiladon's 1+ save is not as good as it was. Skinks are stuck with 5+ save now;
- No way to stack command abilities. Saurus lists really relied on this, especially in Koatl's Claw. Now the worst constellation is nerfed even harder. TL suffered from this too, but to lesser extent. No more double-tapping two bastiladons, but that's it.
- Deciding to use at the double before the roll. However, with lots of CP I feel we won't hesitate to use it. We love run+charge;
- New coherency. Especially hard hit for saurus. But the new editions seems to be designed about buffing Lumineth and destroying Saurus;
- Reinforced units. We really liked large units. Not only it limits our battlelines, but you simply won't have enough reinforcement slots to increase hunting packs, kroxigors, terradons or chameleons;
- New 18 wounds stat is very bad for kroak, since he loses look out. cover and cannot garrison anymore;
- All out attack and all out defense now gives +1 instead of rerolls, which we already had tons of;
- Miscasts. I hated this mechanic in 40k and now we have this one too. It punishes units for what they are designed to do. Absolutely stupid, if you ask me. Probablity of Kroak being slain by own miscast is absurdly low... but never zero;
- New mystic shield and arcane bolt. No more shooting something reliably with d3 mws with kroak. No more reroll 1's for bastiladons, etc.
- Divine wrath. Just because miscasts are not enough;
- Loss of warscroll battalions in matched play hurts saurus and mosnters;
Buffs
- Lots of CP. Our Coalesced armies suffered from lack of CP, and you had to take Kroak because of his CP generation to take what you want.
- Ability to command to own squad will help skinks by a lot. Larger ranges in general is also good. I prefere wholly within 12 to within 6, especially with new coherency. And I hope that Dread Saurian Totema won't be FAQed just for fun;
- Heroic actions are great for us. More CP, healing slann and carnosaurs (too unreliable for stega heroes, unfortunately), finest our is great for reactinary defense, when you feel your important hero will be focused. Also, nothing says that Finest Hour does not affect mounts;
- Redeploy will help us to stop enemy charges/shooting and we will, most likely, have CP for it;
- Unleash hell is great for venomous skinks and salamanders;
- All out attack and all out defense allows us to retain bonuses on multiple units and stack modifiers to ignore negatives;
- New mystic shield and arcane bolt. Multiple accessable +1 to save will lead us to multiple pseudo-invulnerable saves. And now you can hold arcane bolt until you move/charge/get charged, increasing its threat range. More damage in the face is also nice;
- New prayers. Our Priests will love them a lot. 6+ ward without astrolith, healing, curse, banishing invocations. If Starstone staff becomes a prayer too, it is both buff and nerf;
- Monstrous rampages. Nothing to add here;
- New core battalions finally allow us to low drop our army and easy access to second artefact for any constellation;
- Universal Enhancements. All types of enhancements looks very interesting. I can see High Priest trait to be used a lot in thunder lizard for reliable prayers. Amulet of Destiny allows us to make a Stonehorne out of Bastiladon or Carnosaur. Ghost-mist can give additional protection from shooting for our heroes. Both Heal and Curse are very interesting for priest. Finally, we don't need to roll for triumph any more and can chose one for free, or even too, if we badly want to.
- New Mystical terrain rules allow us to get +1 to chanting rolls, making priests very reliable.
My thoughts on winners and losers of units list:
Winners
Slann
Oldblood on Carno
Sunblood
Scar-Veteran on Carno
Preist
Starpriest
Stegadons
EotG
Chief on Stegadon
Stayed the same or sidegrade
Kroak
Scar-Veteran on CO
Astrolith Bearer
Starseer
Oracle
Skinks
Salamanders
Kroxigor
Losers
Guard
Knights
Chameleon skinks
Razordons
Bastiladons
Terradons (chief)
Absolute losers
Oldblood on foot
Eternity warden
Warriors
Ripperdactyls (chief)
As you can see, numbers of pros and cons are very close. Same with winning and losing units. So, I don't think that we will be much weaker, but we are certainly will be very different and our place in meta will mostly be defined by new point costs and how much other armies benifit/lost from new edition. I can see us struggle against high save armies/hero snipers, but we still will be great in monster mash/objective control.
However, you can notice, that without a couple of exceptions, our mediocre or weak units became even worse, while good units stayed the same or great winners.
GW is talking much about diversity in the new edition, but the effect qute the opposite. We could experiment with builds before (what if I take 3 razordons instead of salamanders and overbuff them with all possible abilities? How hard a huge pack of ripprdactyls will hit?), but now we want to take our best stuff and tap our best command abilities on them. Why bother with taking 3 more ripperdactyls, when you can make a unit of two salamanders? Why take chameleon skinks, when you need a skink cohort? And plenty of similar examples.
Overall, I don't even feel that new edition is better it feels just different. It resolves some problems and bring new ones, it gives new possiblities but takes away quite a lot. Can't wait for GHB to finally try it out.