I'm preparing for a little documentary which includes quiet talking in very quiet rooms, some singing indoors and some few (windy to stormy) outdoor scenes. Everything will be done mono, with one single microphone on a boom to bring it in close. I would like to include as much direct ambient sound as possible with hard sound cuts between takes (no underlying separate ambient). Nevertheless, I would like the quality of the recordings to be the best possible.
I read that the omni AT4022 is well regarded by the nature recordists for its low self noise. Also, its cardioid brother, the AT4021, is appreciated for studio recordings, so the sound quality of the omni AT4022, can't be that bad. Also it is smaller and lighter than the NT2-a or NT2000. But the latter are, as you said, also regarded as very good and quiet microphones. Only, they do not seem to fit in any blimp that would be practical for my application, and I would prefer not to purchase both.
My guess is, that the AT4022 is the better option?!