The truth is, your hubscores and profile score as a "hubber" are separate scores. The hubscores are determined by how your hubs are relative to, and link to other similar topics, and thus, its popularity. Also, hubs are rated according to this same overall grading system.
Secondly, The responses that you get, including fan mail will affect your score for all of your hubs in general. However, your profile score is measured by your popularity in the forums and answers forums, the number of times you've commented on other people's hubs, and your popularity. Following this grading system are the Accolades, which are awarded you on the right hand side of your profile page, near the bottom middle section. Hope this helps.