Thanks, Orly, I came to same conclusion about most of those things working with the basic moves as given (as an example, I think interrogation would be covered quite well by a combination of 'go aggro' and 'read a person', with maybe the occasional seize by force thrown in). On my own computer, I have some notes that include the basic moves I think fit with those activities, but I'd figured I'd present them here to see if anybody had some different thoughts from me. I also wanted to make sure any use of the same moves from normal AW is because they're the right moves, and not out of a desire to just 'skin' the game instead of coming up with more fitting stuff.
That's a pretty excellent point about the moral ambiguity angle, one I hadn't really considered. A lot of the rhetoric in the Dark Heresy books says you should be exploring moral issues (like, is it okay to use daemons to fight daemons? or whatever) but the rules do kind of enforce a 'for reals' morality, what with the corruption points and all.
Perhaps a compromise would be to explicitly make corruption "your connection with Chaos" and leave judging that connection more up to the players (though having the end state be "you're so twisted and mutated that you aren't really a person anymore" kind of weights the discussion).
At any rate, I think the key will be to put a lot of focus on the Radical/Puritan split in the inquisition, and be sure to present the radicals as sympathetic, or at least potentially sympathetic, and not just twisted bad guys. Likewise, the scarier side of the puritanical Inquisitors needs to be presented too, so that it doesn't look like a "good guys vs bad guys" kind of thing.
I'm also super excited about the implications of a group of acolyte's inquisitor being mechanically a threat :)
I like your suggestions to add to the list! I thought really hard about putting "investigate" on my own list, but I decided that in a game like this, you probably shouldn't have an investigate move per se, but rather the investigative process should be a combination of read a person/sitch, research, interrogation, and other rolls, since that's one of the 'core activities' of the game. Good call on the bureaucracy and terrorize your lessers moves, though :)
As for the moves you mention that are going to need some work, I think that research will probably look a lot like the "read a ___" (book?) moves, where in fiction you have to have access to the right sources, and success lets you ask questions. Adding in some of the flavor of opening your brain, where a miss makes weird stuff happen to you is also probably good :)
For psychic powers and sorcery, I think these will mostly be covered by custom playbook moves. Maybe make a whole "psyker" playbook and give certain other character types advances that let them take one of those moves. As I think I mentioned above, the spell rules in Apocalypse D&D make for some nice inspiration.
And we've got a whole thread going for go crazy/become twisted and corrupt, so I won't comment further here :)