Yeah, this could help a lot. Scaling based on the past response rate of the sender and how many messages the sender has sent recently would make the pricing more relative, and thus prevent a basic enumeration of "prices of people".

It would also go a long way to not have these prices be listed on a catalog page, but only when clicked into an individual person, so it's less of a feeling of comparison shopping.

The psychology of these UI design things matters a lot.