So, I really have been giving this some thought. I have a few things working here and there. But, from my mentor- I believe it's best to sort the 'pitch' first, by describing the "Desired end state product", but with throw-away place-holder names.
You see, on a shelf, a little book that says "40k Dungeon Crawl: Fun Awesome Campaign". You take this book and it gives you a basic narrative 'introduction' on the back that tells you where this 'campaign' arc takes place, and what kind of terrain players should try to have on hand- if not, simple 'dry erase' mats could suffice. Inside you find that this 'dungeon crawl pack' includes place-holder tokens for the hostiles (real models would certainly be encouraged), and a 'narrative' for many factions- Imperium, Chaos, Aeldari, Drukhari, etc. You and your friends get together and decided which faction your 'team' would like to play as (alternatively, you could each play seperate games as different factions as well). The choices you make determine how this 'campaign' progresses and what occurs. You aren't required to purchase any new models, you can use those from your own collection. Alternatively, this may also encourage you to invest in models and terrain to make the game more immersive.
The short version:
>Take Warcry's combat system, terrain system, and random events/objectives
>Make it '40k'
>Tailored narrative for a variety of factions ("Chaos Marine" story, "Aeldari" Story, etc.)
>Difficulty scaled to 'power level' of Characters
>Reactive enemy AI based on various conditions
>Legacy system- decisions and successes/failures impact events in narrative- multiple narratives can be linked together
No, this is by far not the final product. This is the starting draft and there's just a little bit of playtesting behind it, but options are limited.
I'm open to ideas and recommendations from people here.