Questions: In general, do you think Bitcointalk.org is a friendly place, and/or would you be really comfortable telling close friends (offline, in the real world) that they should come here and sign up?
These questions are two, for the first part of friendliness, No, I don't consider Bitcointalk a friendly place, but it's still not a cruel place either. On a scale of 10, I can still hand it a 3 for clarity's sake.
And for recommending the forum to friends, well, it's a choice and the purpose of signing up on the forum matters. Above all, the forum is engaging and educating, this alone is enough for anyone to sign up on it without regrets.