Be'lakor

Be'lakor is a great choice for the Daemon Codex. As he can grant the Invisibility in every game, it could be a good addition for Grimoire.

Telepathy lore is very good itself and knowledge of all it's Psychic Powers can make many wonderful things with Deamon army and their enemies... Falling back Hive Tyrant, non-shooting Death Star, etc. And he also has Ld10, yeah!

Be'lakor himself is not bad as a fighter - he's immune to Instant Death, Shrouded, fleshbane/armourbane... And a 4++, which can be combined with the Book. He also doesn't have the Daemonic Instability. 

That dude also can be selected as a HQ Choice of the allied CSM.

ARMY DESCRIPTION : Chaos Daemons + Chaos Space Marines

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Lord of Change; Greater Reward; Exalted Reward; Psyker (Mastery Level 3) [305] - Warlord

HQ2 : Heralds of Chaos:

HQ2.1 : Herald of Slaanesh; Steed of Slaanesh; Lesser Reward; Greater Reward; Exalted Locus of Beguilement [120]

HQ2.2 : Herald of Slaanesh; Steed of Slaanesh; Lesser Reward; Greater Reward [90]

HQ2.3 : Herald of Slaanesh; Steed of Slaanesh; Lesser Reward; Greater Reward [90]

Elite1 : 8 Fiends of Slaanesh [280]

Troop1 : 15 Daemonettes of Slaanesh [135]

Troop2 : 14 Daemonettes of Slaanesh [126]

Troop3 : 14 Daemonettes of Slaanesh [126]

Troop4 : 14 Daemonettes of Slaanesh [126]

FORTIFICATION

Fort1 : Aegis Defence Lines [50]

ALLIED DETACHMENT : Chaos Space Marines

HQ1 : Be'lakor [350]

Troop1 : 10 Chaos Cultists [50]

TOTAL [1848]

Keepers of Secrets

That folks could be the great HQ choice, but... They're just Monsters, not the FMC :(

Keepers know the Telepathy lore, which is pretty good one, so, Keeper's main function is a Psyker.

They're not so slow as Uncleans do, thanks to the Slaaneshi run d6+3 and fleet. So, there's no need to put them to reserves. Also, they'll lose a turn of casts, when arrive via Deep Strike, and Keeper is not so tough as Unclean does, so, that could be critical. Also, the Invisibility could be useful, starting from turn1.

So, they need the maximum Mastery Levels and the Greater Rewards to survive a bit longer.

Keepers also make the Slaaneshi DP a Heavy Support Choice.

HQ1 - Lord of Change; Greater Reward; Exalted Reward; Psyker (Mastery Level 3) [305] - Warlord

HQ2 : Keeper of Secrets; Greater Rewards (x2); Psyker (Mastery Level 3) [260]

Troop1 : 15 Daemonettes of Slaanesh [135]

Troop2 : 15 Daemonettes of Slaanesh [135]

Troop3 : 14 Daemonettes of Slaanesh [126]

Troop4 : 14 Daemonettes of Slaanesh [126]

Troop5 : 11 Pink Horrors of Tzeentch [99]

HS1 : Daemon Prince; Daemon of Slaanesh; Warp-Forged Armour; Daemonic Flight; Greater Rewards (x2); Psyker (Mastery Level 3) [330]

HS2 : Daemon Prince; Daemon of Slaanesh; Warp-Forged Armour; Daemonic Flight; Greater Rewards (x2); Psyker (Mastery Level 3) [330]

TOTAL [1846]

Great Unclean Ones

Great Unclean Ones are pretty slow dudes, but are pretty tough. Not the best choice, if you ask me, cause the maneuvrable units rule nowadays.

They're good with 2 Greater Rewards and Biomancy buffs - they just become difficult to kill. A good point to deny some markers. They also can slay tough guys with the Baleswords. Poison, AP2 and Instant Death. It's better to avoid melee with this fella... Ouch!

As they are slow ones, there's a need to send them to deep strike.

Also, Great Unclean Ones (as the Plaguefather do) make the Nurgle Princes to be the HS-choice instead of HQ.

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Great Unclean One; Greater Rewards (x2); Psyker (Mastery Level 3) [280] - Warlord

HQ2 : Lord of Change; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [305]

Troop1 : 11 Pink Horrors of Tzeentch [99]

Troop2 : 11 Pink Horrors of Tzeentch [99]

Troop3 : 11 Pink Horrors of Tzeentch [99]

HS1 : Daemon Prince; Daemon of Nurgle; Warp-Forged Armour; Daemonic Flight; Greater Reward; Exalted Reward; Psyker (Mastery Level 3) [335]

HS2 : Daemon Prince; Daemon of Nurgle; Warp-Forged Armour; Daemonic Flight; Greater Rewards (x2); Psyker (Mastery Level 2) [310]

HS2 : Daemon Prince; Daemon of Nurgle; Warp-Forged Armour; Daemonic Flight; Greater Rewards (x2); Psyker (Mastery Level 2) [310]

TOTAL [1997]

Lords of Change

LoChes are maybe the best Greater Daemon choice. They have worse melee characteristics, then Bloodthirsters and no basic 3+ save. But they are still deadly fighters and, what is very important, they have access to Divination, that make LoChes better warriors, then Thirsters IMHO.

There are 2 variants - Greater and Exalted Reward (It can be the Grimoire, as it can be a table choice) or Lesser and 2 Greater Rewards - and the Staff of Change on the Lesser one almost always.

Divination make LoChes pretty universal - as they are support units and fighters at the same time. And don't forget, that Lords of Change (and Kairos) make Tzeentch Princes the HS choice.

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Lord of Change; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [305] - Warlord

HQ2 : Lord of Change; Lesser Greater Reward; Exalted Reward; Psyker (Mastery Level 3) [305]

Troop1 : 12 Pink Horrors of Tzeentch [108]

Troop2 : 12 Pink Horrors of Tzeentch [108]

Troop3 : 12 Pink Horrors of Tzeentch [108]

HS1 : Daemon Prince; Daemon of Tzeentch; Warp-Forged Armour; Daemonic Flight; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [355]

HS2 : Daemon Prince; Daemon of Tzeentch; Warp-Forged Armour; Daemonic Flight; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [355]

HS3 : Daemon Prince; Daemon of Tzeentch; Warp-Forged Armour; Daemonic Flight; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [355]

TOTAL [1999]

Bloodthirsters

The Bloodthirster has an advantage before most HQ Choices for just being the Flying Monstrous Creature. As GUO and Keeper cannot swoop, but cost almost the same points...

A strong point of Bloodthirsters is their basic 3+ armour save. This allows them to take the Grimoire + Greater Reward without any questions, as Lord of Change, for example, is pretty much better with 2 Greater Rewards. But, 2 GRs are still god for the Thirsters. How about lesser reward? Why not, he could capture Warp Breath, or take axe to Instantly kill the dudes like Wraithknights.

Also, they are pretty deadly in melee, with WS10, I9...

Don't forget that Bloodthirsters (including Skarbrand) make Khorne Princes a HS-choice.

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Lord of Change; Lesser Reward; Greater Rewards (x2); Psyker (Mastery Level 3) [305] - Warlord

HQ2 : Bloodthirster; Greater Reward; Exalted Reward [300]

Troop1 : 16 Daemonettes of Slaanesh [144]

Troop2 : 16 Daemonettes of Slaanesh [144]

Troop3 : 16 Daemonettes of Slaanesh [144]

Troop4 : 16 Daemonettes of Slaanesh [144]

FA1 : 11 Flesh Hounds of Khorne [176]

FA2 : 11 Flesh Hounds of Khorne [176]

HS1 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

HS2 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

HS3 : Skull Cannon of Khorne [125]

TOTAL [1998]

Ku'Gath Plaguefather

So, it's Plaguefather's turn. Actually, he's less useful, then Kairos and even Skarbrand.

But, he still has a good point. As an Immortal Commander, he allows units within 12" to re-roll the Instability Tests. That means, the army around him must fight in melee. He's not needed on the table in 1st turn and he's also a slowpoke... So, the Deep Strike is his choice. That means, we must take some Plague Drones with Icon and maybe the reserve control.

He's not bad as anti-infantry shooting unit... But, range is low and he doesn't ignore cover. With the Plague Wind, he gets a 2nd blast, and he can fire both, as he's a monster.

And about regaining a single wound to the single Nurgling base... IMHO, absolutely useless feature :(

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Ku'gath Plaguefather [260] - Warlord

HQ2 : Heralds of Chaos:

HQ2.1 : Herald of Tzeentch; Disc of Tzeentch; Exalted Reward; Psyker (Mastery Level 3) [150]

HQ2.2 : Herald of Tzeentch; Disc of Tzeentch; Psyker (Mastery Level 3) [120]

HQ2.3 : Herald of Khorne; Juggernaut of Khorne; Lesser Reward; Greater Reward; Exalted Locus of Wrath [155]

HQ2.4 : Herald of Khorne; Juggernaut of Khorne; Lesser Reward; Greater Reward [130]

Troop1 : 11 Pink Horrors of Tzeentch; Instrument of Chaos [109]

Troop2 : 11 Pink Horrors of Tzeentch [99]

Troop3 : 11 Pink Horrors of Tzeentch [99]

FA1 : 9 Screamers of Tzeentch [225]

FA2 : 17 Flesh Hounds of Khorne [272]

FA3 : 3 Plague Drones of Nurgle; Icon of Chaos; Plaguebringer; Greater Reward [161]

FORTIFICATION

Fort1 : Aegis Defence Lines; Comms Relay [70]

TOTAL [1850]

Kairos Fateweaver

Kairos - one of the best HQ-choices in a codex. He allows a re-roll of a single d6 once a turn, which could be used with a Grimoire of True Names, Portalglyph, Ground Tests, failed Psy-tests, armour penetration, etc. He also grants us the best Warlord Trait for the CD Army - re-roll of the Warp Storm table. In my opinion, there only need to re-roll first 3 variants. You may also re-roll a single die in that Storm - with a Staff of Tomorrow, instead of a Trait re-roll - to try to get the needed result. For example, you rolled 6 - 1. You can re-roll "1" to get better result, as you never get something less then 7.

Fateweaver also has 4++ and re-roll of 1s on saves, which can be combined with the Book.

But... It's only his adavantages. He's almost nothing in melee, has a single roll on 4 schools, which is almost nothing. Yes, he has a good potential for shooting with Tzeentch lore... But, if he will fly across the battlefield, shooting the enemy... He wil automatically become the primary target. With his T5 it's difficult to survive normal shooting... So, it's better to hide him.

In rosters, such as Deathstar, where the re-roll is needed like air, he's a must-have choice.

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Kairos Fateweaver [300] - Warlord

HQ2 : Heralds of Chaos:

HQ2.1 : Herald of Tzeentch; Disc of Tzeentch; Exalted Reward; Psyker (Mastery Level 3) [150]

HQ2.2 : Herald of Tzeentch; Disc of Tzeentch; Exalted Reward; Psyker (Mastery Level 3) [150]

HQ2.3 : Herald of Tzeentch; Disc of Tzeentch; Exalted Locus of Conjuration; Psyker (Mastery Level 3) [145]

HQ2.4 : Herald of Tzeentch; Disc of Tzeentch; Psyker (Mastery Level 3) [120]

Troop1 : 11 Pink Horrors of Tzeentch; Iridescent Horror [104]

Troop2 : 11 Pink Horrors of Tzeentch; Iridescent Horror [104]

Troop3 : 10 Bloodletters of Khorne [100]

FA1 : 9 Screamers of Tzeentch [225]

HS1 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

HS2 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

FORTIFICATION

Fort1 : Imperial Bastion; Icarus Lascannon [110]

TOTAL [1848]

Skarbrand

So, the Skarbrand. The Bloodthirster... Without wings. Actually, it's a big minus of him - that he's not a FMC, just a Monster. He's nor able to maneuver, nor to survive...

As a Warlord, he's deadly in HTH... But, who will let him in CC?

As for his rage/fury ability, it's good for non-Khorne melee units... As for Khorne, they can benefit one of that rules with the Locus, so it's a shame... Cause, if there are Flesh Hounds, for example, they will probably be with Herald.

Maybe, he must arrive with Deep Strike, and maybe you need a pack of Bloodcrushers with Icon for him. And also, you must control the reserves. Instruments/comms relay?

Example roster with Skarbrand.

ARMY DESCRIPTION : Chaos Daemons

PRIMARY DETACHMENT : Chaos Daemons

HQ1 : Skarbrand [225] - Warlord

HQ2 : Heralds of Chaos

HQ2.1 : Herald of Nurgle; Palanquin of Nurgle; Exalted Reward [115]

HQ2.2 : Herald of Nurgle; Palanquin of Nurgle; Greater Locus of Fecundity; Greater Reward [130]

HQ2.3 : Epidemius [110]

Elites1 : 3 Bloodcrushers of Khorne; Icon of Chaos; Bloodhunter [150]

Troop1 : 11 Pink Horrors of Tzeentch [99]

Troop2 : 14 Daemonettes of Slaanesh; Instrument of Chaos [136]

Troop3 : 14 Daemonettes of Slaanesh; Instrument of Chaos [136]

Troop4 : 15 Daemonettes of Slaanesh [135]

FA1 : 7 Plague Drones of Nurgle; Venom Stings; Plaguebringer; Greater Reward [354]

HS1 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

HS2 : Soul Grinder; Daemon of Slaanesh; Baleful Torrent [170]

FORTIFICATION

Fort1 : Aegis Defence Lines; Comms Relay [70]

TOTAL [2000]