Just thought I'd bring this back to the fore, as I've begun work on it once again. Just uploaded it's last version and thought I'd see what the general consensus is.
There are somethings I'm keen to represent - and that's the fact that Chaos Strikes anywhere - and the fact that none are safe. As such, the rules which were normally intended to be good only against Daemons, are now effective against Chaos Daemons, Chaos Space Marines, Space Marines, Imperial Guard, Witch Hunters, Daemonhunters, Ordo Malleus (refers to 3rd edition and this codex respectively), and Ordo Xenos (I'd had plans to write a codex for these as well).
However, the beauty of the rules for the "Daemonhunter" rule, as I called this, would only trigger against Daemonhunters and Ordo Malleus if there were no models with the Grey Knight special rule present in the army.
I've attempted to get allies back into the game, by including them as just vanilla units - so you can have your Space Marine Captain, Imperial Guard Command Squad etc - although they are looking to be fairly weak compared to units such as the Grand Master who I'm quite proud of, if I say the least.
I've attempted to get the Inq Mandate present in another manner as well, by allowing them to use any vehicle as a transport.
The units I'm quite proud of are the Inquisitor Lords and their Retinues (especially the Daemonhosts, which do a nice job of counteracting the hole that a lack of Grey Knights costs), Grey Knight Grand Masters (esp Mandulis - he's an absolute monster - 7 S6 attacks on the charge, which ignore one base contact opponents Eternal Warrior special rule, coupled with rolling 2D6 for penetration, 2+/3++ Save, and a Psychic Hood, in addition to the Grey Knight rules - Preferred enemy versus opponents listed above, Scoring unit if his retinue end with 5+ models, +1 Combat Resolution against listed opponents, fearless, and reroll failed armour saves versus no retreat wounds), Land Raider Helios, Arbites Squads, the Emperors Tarot and Repressors Water Cannons
I think I'm making the Grey Knights worth their 25pt cost now - I didn't want to reduce their cost so that they became spammable, but rather upped their abilities to be worth it.
A few upgrades have been put in - such as for the LR Helios, it can now fire Castellan missiles, except those missiles bypass cover and invulnerable, and Hyperios missiles have the Hunter Killer aspect of the Hydra as well as Heavy 2, Psycannon Bolts for LRC's, smoothed out the Wrist Mounted Storm Bolters, Psycannons are now just a solid 24" Assault 3 S6 weapon, ignoring 4+ AS and Invulnerable, Psycannon Bolts now are available for BP's, Bolters and Storm Bolters, as are Hellfire rounds,
Certain things need going over - such as the Grand Masters Diabolous Extremis, and the Psychic Powers, and potentially Grimoire of Truenames - they can have a 12" Radius reducing all WS to 1 etc.
The Brother Captain is overcosted - by a good 30-40 points, and the Inducted Command Squad shows the Space Marine copy paste from above.
Anyway, here's the list WIP.
The list is looking along the lines of the following:
Inq Lord (Puritan/Radical) with Retinue
Grey Knight Grand Master
Grey Knight Brother Captain
Space Marine Captain and Command Squad
Inducted Guard Command Section
Inquisitor Lord Hector Rex (Puritan)
Inquisitor Lord Quixos (Radical)
GKGM Ganelon (Dreadnought)
Artekus Bardane (Radical)
Lone Daemonhosts (Radical)
SM Dreads (no ironclad or ven)
Inq Land Raider
Inq LR Prometheus
Inq Razorback (Incinerators/Psycannons)
PAGK capable of attacking from Deep Strike and can be armed with TH/SS or LC's.
Inq ST Assault Squads - DSing ST's with CCW's, can assault from Vehicles etc.
SM Assault Squads
GK Purgation Squads - Has fire discipline, but Long Fangs have that, so are getting the ability to switch their weapons into heavier versions - i.e Multimeltas (which ignore Invulnerable =/) etc.
GK Dreadnoughts (All Venerable)
Orbital Bombardment - just a straight purchase - if 1 or more Inq or GK unit is pinned voluntarily or not, they can call down the coordinates for a bombardment. if none pinned can choose to voluntarily take cover, giving up shooting to call it down. LRPrometheus on the other hand automatically call it down, regardless of whether or not friendlies are taking cover
So there's a lot to go, what do you all think? I appreciate your feedback.