I see your point on the calculated horror not being horrific in the books, and I think that is one aspect as to what makes the books funny. The bureaucracy calculating out the level of bad, regardless of the outcome. but we all know that bad is bad, and it should be stopped. The bureaucracy makes the books funny in between outings and jaunts, but could be glossed over in a game situation. That being said, I was going to mostly ignore the inter-office stuff - except if a character took an 'enemy' hindrance, it'd be someone in HR or something.
I was mostly thinking of the computational summoning aspect. Cthulhu (or whatever) via heavy math, brought upon at high speeds via computer processing. Math is the new Magic.
And I think Stross does a lot of what Lovecraft did - you don't get descriptions of creatures, he keeps it vague. But the world-coming-to-an-end-unless-we-stop-the-big-bad aspect is there in most of the stories.
This is the crux of the AoE, to me, getting the big-bad. Or rather, preventing it. Almost all RPG's have this aspect, maybe not earth destruction as an outcome, but some big bad thing - bomb, plague, Tribbles (oh, said plague already), etc.
Additionally, I like the spin on devices - like the Smart phone protection fields and what not. Easily brought into AoE as equipment, just a humorous flavor by using the iPhone - I need an anti-dimensional dampener! oh, Brains wrote an app for that. Shiny!
I think that Stross was influenced by Bond and Q (Iain Fleming) for some of these items..