To alter the reviewer recommendation options, see e.g. this thread
. It's pretty old but still relevant.
To bring an average into the track director's interface, you'll have to do some fancy MySQL footwork. There is some related discussion here
Note that both of these posts are OJS-related; to adapt to OCS is usually just a matter of changing terminology: Sections in OJS are Tracks in OCS; likewise Editors are Directors, Articles are Papers, etc.
Public Knowledge Project Team