Also, it would be nice to require some payment (very small) to start an account here. Currently, many create accounts and let is age to sell later.
I think it's bad idea. I'm not sure that it would kill account sales market, but it would definitely stop legitimate newbies from cresting account here when they will see that payment is needed to join forum.
Maybe it would be better to make signatures as paid privillege - users would have to pay some BTC to enable signatures in their profiles.