Semi-regulars from the MG side were decently represented; Bill Daily, Jimmie Walker, McLean Stevenson, Marcia Wallace, Dick Martin, Gary Burghoff, Nipsey Russell, Elaine Joyce and Fannie Flagg all appeared on at least one week. Brett didn't participate, but it doesn't seem that she made any TV appearances from 1982 to 1990.
Unless you count Walker, Stevenson and Wallace (along with Gobel), the HS side didn't have as many previous regulars -- although since MGHSH was being packaged by Goodson, it may be that they simply turned to celebs they had booked most often for other shows, and didn't call on those who rarely did Goodson games, like Vincent Price or Charo. Others, like Karen Valentine and Sandy Duncan, seemingly weren't doing many game shows by that point.