I would probably pick Seven Swords Zabuza as well, for that control on top of the double attack. Normal Zabuza's clone can be killed pretty easily and then you lose that second attack, plus his mystery only works on standard attacks.

I would agree the issue with normal Zabuza on a team that isn't solely water is that he blinds your team as well. Which totally defeats the purpose of if you're not running a full water team. On top of that, it's difficult to run a full water team that also does enough damage.