I've done a lot of candidate interviews in the past, and your #3 question is killer - Almost nobody asks that question during interviews; the ones that have ask

I've done a lot of candidate interviews in the past, and your #3 question is killer - Almost nobody asks that question during interviews; the ones that have asked it have almost always gotten an offer. (In that they have almost always been the highest quality candidates anyways.) Beyond that, I like to ask about the longevity of the people that I'll be working with; i.e. "What is your turn-over rate like?" or "What is the average number of years people on this team have worked here?" I've found that turnover is a pretty decent indicator of employee happiness. The lower the better, of course.