Using Wild Talents as the baseline (For easy power/technology creation.), here are a few changes I'd implement:

Trim the Skill list - This is very much a taste thing, but I find the WT skill list too bloated, especially for the cost of skills. Something like Reigns skill list, where every stat has about 5-6 skills under it and thus costs five times as much as a skill works better for me. So a bunch of skills would be combined and a couple of new ones would be stolen from Reign, especially the Sense skills.

Add the Madness Meter from Nemesis/UA - I love the UA Madness Meter and I think it would work great for a 40k game, where Madness and characters hardened by war are featured quite often. Also, it's easy to both add and remove it, depending on the tone somebody's aiming for.

Shattered Hopes demo
Scenario by Rob Schwalb

Make ready your chainsword, strap on your bolter, and say a prayer to the God-Emperor, for Warhammer 40,000: Dark Heresy is here. Step into the role of an agent of the Inquisition, hunting out and destroying the foul and twisted influence of Chaos.

This free booklet gives you a taste of the fantastic new roleplay game from award winning publisher Black Industries. The long awaited Warhammer 40,000 Roleplay: Dark Heresy will be available from February 2008.

Download the Scenario - 9.65 MB PDF Download
Download a Compressed Version of the Scenario - 5.86 MB PDF Download

Steal TSOYs "Keys" to replace the XP system - Again a taste thing, but I find WT/Reigns XP System pretty boring. Not really bad but not terribly exciting either, so something more interesting would be nice. Enter TSOY and its Keys. They'd allow p_layer_s to better define what they want out of the game and to actually decide what they want to earn XP for. Also, Buyoffs make for an awesome character change mechanic. ("Oh, fuck this protecting people shit, Chaos doesn't look so bad now. I lose the Key of Compassion and get the Key of the Heretic instead!") Also, eyeballing the Costs of Wild Talents, having characters earn 5-10 XP per session, maybe less with a modified 1-2-3 spread for Keys, seems to fit alright... (I'd like characters to get at least one "Goodie" per session, wether its a skill point or whatever.)

Pre-stat a bunch of 40k Stuff - Describing various things we see in 40k in WT terms doesn't seem too hard. Weapons are pretty easy: Lasguns of various sorts seem to be about as effective as various modern day guns, so a Laspistol might have Width in Shock+Killing, a Lasrifle Width+2 with a few levels of Spray and/or Penetration, Flamers and various Plasma weapons would have Burn and big damage and so on.

Various races/monsters/occupations also wouldn't be hard to translate. Orks would get lots of strength, a bunch of Extra Tough levels, maybe a bit of Heavy Armor, the permament Size Shift mentioned on WT Page 111 and I'd have the perverse itch to give them some power _base_d on Second Chance, either representing the fact that they're too dumb to die or the next generation of Orks that grew from their spores. (But then I'm wierd.) Tau scream for many Foki to represent Battle Armor and High Tech Gadgetry, as do Adepts of the Machine God. (Who are also the perfect fit for the Gadgeteer power.) Psykers could be statted with things like Telepathy, Harm, Precognition, Telekinesis and Ghost, adding a few defects/intrinsics to represent the danger of posession and other nasties.

Depending on what exactly I'd want to run (Rogue Traders, Imperial Guard, Inquisitors, ...) different things would need statting. In an IG game, few people would need to think about Psyker Powers or Demons. (But then, who knows...)

Example character from Shattered Hopes demo

Name: Mir You hail from the deadly world of Fedrid, whose forests are so dense and so full of dangerous predators, the Imperium trictly forbids offworlders from descending on the planet without a licence. Indeed, it’s a wonder that your people have survived, so hostile is Fedrid to human life. Somehow, your tribes managed and established small kolonies formed out of a need for mutual defence.

Unfortunately, your efforts are often for naught, for the Imperium culls the best and brightest warriors from your tribes to fill the ranks of the Imperial Guard, which was how you found yourself removed from everything you knew and battling for your life against horrid xenos and the shrieking tide of Chaos.

You found the work of a Guardsman specially suited to you; your fighting skills honed by fighting sabre cats, blood wolves and worse on Fedrid, and it wasn’t long before you attracted the attention of Lord Inquisitor Anton Zerbe of the Ordo Hereticus. Impressed by your zeal, natural toughness, and ability to take orders, he lifted you from the faceless throng of Guardsmen and gave you a place in his retinue. Having only served your master for a few weeks, you are not yet comfortable with your duties and wonder where fate will take you.

You are a rangy young man with fair skin, long brown hair and linty grey eyes. Whorls and geometric symbols cover your flesh, tribal tattoos you gained as a right of passage to adulthood. You still wear the uniform of your battalion, a camoulaged suite of fatigues and thick jungle boots, but you’ve worked in a number of disturbing trophies taken from your enemies — fingers, locks of hair, and scraps of clothing. You believe that by taking a trophy from a vanquished foe, you gain ownership over his soul.

Point Total: 160 seemed like a good fit, although 180-200 might be closer to my prefered level of power.

Archetype: This would probably be a good place to either introduce various setting archetypes (Imperial Guard, ...) or "splats" (Unmodified human, Space Marine, Xenos, ...), but for now, I'll just leave that alone, instead buying intrinsics as normal powers if necessary.

Stats:
Body: 4
Coordination: 3
Sense: 3
Brains: 2
Cool: 3
Command: 2

Skills: - Here I used the regular WT costs with a Reign-like Skill list. Most should be self-explanatory, though.
Fight 4
Guns 2
Parry 2
Vigor 3
Athletics 3
Stealth 4
Dodge 3
Climb 2
Intimidate 3
Direction 3
Sight 3
Eerie 2
Lore 2
Healing 1
Expert: Hunter 3
Equilibrium 3

Powers:
Extra Tough lv1

Madness Meter: (Hardened/Failed) - Here, inspired by the rules in Nemesis, I ruled that voluntary Hardened notches gave back two points and voluntary Failed notches gave back four points. If I really planned to run a campaign, I'd have to tweak these numbers to see if they actually work.
Violence: 4/1
Self:0/0
Unnatural: 1/1
Helplessness: 0/0

Keys: - I gave him two Keys without charging anything, although I figure if I were to run this I'd probably let players buy additional Keys at two-five points. Also, I just grabbed two Keys that seemed to fit without being verly concerned to "get it right". In a real game, I'd work with the player to make up Keys that really do what he wants.
- Key of Bloodlust
- Key of the Lost Child

Equipment:
Long Las (Width+2 SK, Penetration 3)
Axe (Width+1 K)
Las Pistol (Width SK)
Guard Flak Armor (Like a Kevlar Vest with a Riot Helmet, ie. 2 HAR+ 2 LAR on 7-9, 1 HAR+ 1 LAR on 10)
Uplifting Primer, Rations, Battle Trophies, Uniform

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