I have installed the SMF Trader System. It looks nice, but there are better uses for such mod.
I am not totally sure if I understood it. You can rate a post? But only from the Profile from an user or am I wrong or did I install it incorrectly?
Anyhow, I would change the name Trade into Feedback and use it to collect points (like with Karma) for the posts of users and do something with the collected points.
I use Karma for one of my boards (Writing Center III), I renamed it Magic. The SHow module valuta is Galleons and it fits perfectly with the world of Harry Potter. The magic (Karma) works also fine, but can't integrate it fully with each other.
The SMF Trader System might fill that gap.