Moderators have "moderator" under their name, Admin "Administrator", etc. I think Sponsors who support the site should get "sponsor" under their name. To let everyone know who the backbone of this site is.
Another suggestion. This might be too drastic of a change, but hell. In the GP section, give only the sponsors authority to make new threads in that section, and put a "sticky" on the top where members can suggest GPs, and reset it every week or so just to keep things clean.