Wait. Droite commented? That means two things. The commenter is a girl, which is already extremely interesting, and that she looks like Droite... oh God.
I'd say canonically Barian Shark is stronger than Yuma if he went all out and wasn't emotional (since that's the only reason Yuma beat him), so Barian Shark.
Depends on the situation. At their best it could go either way. Kite did beat Shark back in the first season though Shark had no numbers at the time. If you include when he became Nasch I think Shark would be able to edge out a victory over Kite by using Number 101 Silent Honor Ark or Dark to steal Galaxy eyes from him. But it could go either way.