As a longtime New Frontier fan, I tend to view NF as my "prime continuity" - after all, NF has had an internally consistent continuity since 97, way before the other trek lines.
I know some readers find the plots far-fetched, but I don't think there's anything in there more outlandish than TOS. IIRC, in one novel some admirals express the opinion that Calhoun's adventures can't be real, and when its pointed out that Kirk reported far wilder things, they say they think Kirk falsified his reports as well.
Oh, I don't mind the oddities of the stuff that happen in NF. I think the plotlines are a bit comic bookey and sometimes feel like Peter David is writing the Star Trek future of the Marvel universe versus the Star Trek future of the Star Trek future (Jean Grey should merge with the Great Bird of the Galaxy is all I'm saying) but I accept Gangster Planet, Nazi Planet, and all other manner of silliness from the six series.
The only reason I say it's Broad Strokes in my head is more the fact the crew's professional behavior is so utterly and completely skewed. It makes for great and entertaining reading but I have difficulty buying them as Starfleet officers sometimes.
I wouldn't be a Novelverse fan if not for NF, though.
I don't remember exactly what brought them about, but I was already starting to feel that way about NF before BMB came out.
On a personal note, I love New Frontier but it saddens me to no end that "Blind Man's Bluff" is the seeming end of NF both for contractual and personal reasons. It's such a....depressing place to end the series.
Then again, I'm a Xyon/Kallinda fan.