I love using Geese in the game but I don't play as him when I go against other players 'cause of his cheesiness. After that, Dan Hibiki is another favorite of mine, you don't mess with Saikyo style.
Orochi Iori, I've always thought he had a cool design. Something about his blood driving him made, the need for destruction, the drool, and his constant screaming entertains me greatly.
Geese and Violent Ken seem to be the faves here in the consensus and I agree. Violent Ken is the Ken I always wondered if Capcom would create after seeing SNK turn Iori into Orochi Iori and such. Geese is just a badass period.