You guys are missing their big weakness... points cost! If Chaos Warriors cost what Witch Elves or Savage Orcs cost, they would be obscene. However, of all the units I named, a properly tooled up Chaos Warrior is the most expensive points-wise (and by a fair margin at that).
So while the Chaos Warriors appear to have no weaknesses in terms of attacks, initiative, strength or toughness, they will almost always be outnumbered by an infantry unit of equal points cost. So their deficit comes by way of a unit's total wound count. Having more models/wounds in a unit can very quickly offset profile deficiencies in terms of attacks or toughness or armor...
- Witch Elves have no armour and T3, but they have more wounds to soak up damage (and they have ASF to strike before their opponents)
- Executioners only have 1 attack each, but they have more models in the unit with which to attack with (this is doubly true for White Lions who get to attack in an extra rank)
- Savage Orc Big'uns have much poorer initiative than Chaos Warriors and typically strike after their opponents, but they have the models to soak up the incoming wounds and retain combat effectiveness for when it is their turn to strike
We saw it time and time again in the tournament, Chaos Warriors simply did not have enough models to hang in the fight. They too quickly lost combat efficiency once casualties starting rolling in and then broke from combat as they didn't even have Steadfast to fall back on.
Also, if the Dark Elves units taught us anything, special rules like ASF, poison and murderous prowess can win you the day despite having weak stats.
At the end of the day, everything comes down to how good something is in relation to their points cost. Make a K'daai Destroyer 700 points and it is a steaming pile of garbage. Make a lowly TK Skeleton Warrior 1 point a model, and Tomb Kings instantly become a broken army. Chaos Warriors are very powerful, but they pay a very heavy price for that power.
Not in most cases. The most abundant ASF in the game of Warhammer is found among the Elves, who usually sport at least initiative 5. They get their re-rolls from their ASF as long as their initiative is
equal to or better than that of their opponent. So Chaos Warriors can't negate the re-rolls to hit from your typical pointy eared troublemakers.
All great options, but more points, more points, more points! Our tournament contestant Nurgle CWs with Halberds come in at a mighty 18 points a model. In contrast, a Witch Elf tips the scales at only 11 points. Beasts of Nurgle only cost 15 points per wound!
I play Warriors of Chaos and I used to spend a fair bit of time over at the Chamber of the Everchosen (which is why I had a couple years long hiatus here), and I can tell you that Chaos Warriors are not usually the keys to our victory. The WoC army is extremely strong, but it is in elements like DPs, Hortennse Lords, Skullcrushers, Chimeras, Trolls, (and perhaps even things like Hellcannons or Gorebeast chariots) that victory is ultimately achieved.
There were quite a few players who deliberately steered clear from fielding Chaos Warriors because of their belief that they simply weren't that great for their points. As a result there were chariot heavy lists with no Warriors in them. Personally, I wouldn't go that far, but I'd very quickly trade them out for Witch Elves or Executioners if I could!
Also, you don't hear as many exploits from Chaos Warrior Deathstars as you do from something like the infamous Gut-star.