Some other charachters were Shaggy's eccentric relatives, which were some of the best guest stars.
Then there were Daphne's rich uncles and aunts, who all had prominent rich jobs. There were Velma's uncles and aunts, who were all scientists and doctors. Fred's one relative was Uncle Eddie, who ran a newspaper. Then came the real disaster. SCrappy.
I could write a whole essay on why I hate this guy, but I won't. Suffice to say, he ruined the show. I wish we could just all burn everything with SCrappy in it, and pretend none of it ever happened. He shouts out "Puppy Power!" at random intervals, which makes me cringe. He screams "Let me at 'em! I'll SPLAT 'em!" whenever he sees anyone. He worships Scooby, forcing Scooby into roles he's not meant to play. He is incredibly annoying, and often makes all sorts of trouble with his stupid traps and childish antics. I could have never imagined that this could happen to such a great show as Scooby Doo, but I was wrong. SCrappy totally ruined the show. It became boring, tasteless, and unfunny. These dark ages when SCrappy prevailed was when the show fell into the shadows of obscurity and lost many of it's viewers. Finally, someone at HB wised up and stopped SCrappy. Warner brothers bought Hanna barbera, and Scooby Doo stopped production, almost mercifully. The show stayed quiet after that, until Scooby Doo on Zombie Island, by Glenn Leopold, who wrote for both Johnny Quest and SWAT Kats, two great series. If Warner Brothers remembers that they still own HB, they just might release another series... More info about The Great Scooby Renassiance, when the next series starts.