That would depend on the basis for your suspicion. If you didn't like the way he dressed or that he stayed up nights, you would be blown off. If you reported that you smelled chemical ordors coming from his house, and that there was an undue amount of traffic in and out of his front door, that would be the "articulated" part of the suspicion. The first set of circumstances does not, in itself, indicate any illegal activity. The second is typical of a meth lab.

I believe that anyone with an unexplained interest in the number of flight crew members or other procedures not normally known to passengers would be a matter of interest to the FAMs, and if I were a FAM, I would be taking a closer look at the passenger that asked. If I were provided a reasonable explanation for the interest, I'd let it go. In order to investigate, one usually has to ask questions, and people with no ill motive typically answer them.