I think enough information would be gleaned from total BTC spent (which we currently cannot see) as the only statistical addition on buyer side. If someone has 50 transactions but only 30BTC spent that's a "move on" buyer.That's the only addition I would ask for.I also check user number and keep track of how many people have signed up for the site. If I see someone who's "two weeks old" with 20 transactions, I usually ask them to get a substance vendor they have done business with to send me a PM and vouch. If I can't get it, I won't do business.