Andarius's 7th edition daemons 2000 points

Believe me this took a little bit of thought on my part, this will be my new list after I get the parts to implement it.

HQ

Herald of Khorne
Greater Reward
Greater Locus of Fury

Herald of Nurgle
Mastery 1
Loci of Fecundity

Herald of Slaanesh
Mastery 1
Exalted Locus of Beguilement

Herald of Tzeentch
Mastery 2
Exalted Locus of Conjuration

390 points

Elites

Bloodcrushers of Khorne (x5)
Banner of Blood
Instrument of Chaos

Flamers of Tzeentch (x5)

365 points

Troops

Bloodletters of Khorne (x20)
Banner of Blood
Instrument of Chaos

Plaguebearers of Nurgle (x20)
Plague Banner
Instrument of Chaos

Daemonettes of Slaanesh (x20)
Rapturous Standard
Instrument of Chaos

Pink Horrors of Tzeentch (x20)
Blazing Standard
Instrument of Chaos

840 points

Fast
Seekers of Slaanesh (x10)
Rapturous Standard
Instrument of Chaos

Plague Drones of Nurgle (x5)
Plague Banner
Instrument of Chaos
Death Heads

405 points
2000 total

The heralds will be attached to the 20 man squads they are aligned to, each herald that's a psyker will be given their own psychic powers from the daemon list except the tzeentch herald which will have the malefic powers from the core rulebook. This way the pink horrors have the full list of tzeentch powers and I'll have the ability to summon daemons on the fly or empower the ones I currently have.

I'll also be making custom made greater daemons that might be summoned during the game, one for each chaos god, so this will be a fun project.

your list lacks some sort of punch, while 20 bloodletters sounds scary they are just t3 models with a 3++ and are very, very slow on the way towards the enemy.

your only good melee units are currently the daemonettes and the seekers. they are the only ones able to get quickly to the enemy.
the contra to them is that both are very fragile on their own. the seekers are fast but to few to make it over the field, especially without a herald

to keep your theme but buff it up a bit:

-drop those 20 daemonettes, push the seekers up to 20 including a champion upgrade with a lesser gift, so you got another save ap 2 weapon apart from the rending which are now even scarier in challenges.

-give the herald a steed of slaanesh, this gives her a fast movement over the board to acompany the seekers. moving 12" and then running a additional rerollable d6+6" makes it easy for a turn 2 charge. in addition you gain +1 attack, a additional hammer of wrath attack and outflank + acute senses, which carries over to your unit of seekers if you wish to make use of that.

-push the herald of slaanesh psyker mastery level 2. that grants you 2 rolls in telepathy + the primaris power of slaanesh, so the odds are good of getting either invisibility or shrouding. which will increase the durability of the seekers by a lot.

-give him an additional lesser gift for a cheap ap 2 weapon in case you roll a good result on the greater gift. like the 4+ feel no pain or invul reroll on your your herald of slaanesh, in which case you dont really want to swap it for the weapon. if you roll a crap result ont he greater gift, grab 2 weapons. so you also gain a additional attack, which makes your herald 6-7 attacks + 1 hammer of wrath attack on the charge

-either keep the icon or swap for the swiftness one. both are good. the swiftness one however makes it safer to reach the enemy as it grants move through cover. which automatically lets you pass dangerous terrain tests with your unit (every move through terrain is dangerous for cav).

depending if you swap the icon on the herald of slaanesh you now got 25-35 points left over, which you can put either in an additional mastery level on the nurgle herald (if you only got 25 points) or a exhalted reward for the herald of tzeentch, which you can convert to the portal glyph. that way you can get free additional daemons of your choice that, in case of horrors also push your warp charge pool in addition to some additional powers. the portal glyph does not need a psychic test which is awesome. put it in some corner of your board and you are good to go since it cannot scatter over the board edge. for the remaining 5 points you could add another champion in a unit of your choice.

Hmm... I'd still prefer the theme of 1 herald, 1 troop and 1 elite/fast/heavy per chaos god but you do bring up a good point Souba, I could down-size my daemonettes to a ten man group to increase the number of seekers I have then update my herald of Slaanesh with a mount. I'll have to juggle around a few points here and there.

OK here's my revision, its a little more loaded up with weapons so the number of units will be smaller, still it should give a nasty punch.

HQ
Herald of Khorne
Greater Reward
Greater Locus of Fury
Juggernaut of Khorne

Herald of Nurgle
Lesser Reward
Mastery 1
Loci of Fecundicy

Herald of Slaanesh
Greater Reward
Mastery 1
Exalted Locus of Beguilment
Steed of Slaanesh

Herald of Tzeentch
Mastery 2
Exalted Locus of Conjuration
480 points

Elites
Bloodcrushers of Khorne (x4)
Banner of Blood
Instrument of Chaos

Flamers of Tzeentch (x4)
Flamers of Tzeentch (x4)
389 points

Troops
Bloodletters of Khorne (x10)
Banner of Blood
Instrument of Chaos
Blood Reaper
Lesser Reward

Daemonettes of Slaanesh (x10)
Rapturous Standard
Instrument of Chaos
Alluress
Lesser Reward

Plaguebearers of Nurgle (x10)
Plague Banner
Instrument of Chaos

Pink Horrors of Tzeentch (x20)
Blazing Standard
Instrument of Chaos
590 points

Fast
Seekers of Slaanesh (x19)
Rapturous Standard
Instrument of Chaos

Plague Drones of Nurgle (x5)
Plague Banner
Instrument of Chaos
Death Heads
Plague Bringer
Greater Reward
538 points
1997 total

The herald of Khorne will be attached to the blood crushers for added punch and the herald of Slaanesh will join the expanded seekers group, the two 20 man daemon groups will have a herald of their own and the two 10 man groups have champions armed with lesser gifts to add some punch.