I would say Shikamaru then Kurenai. Shikamaru and Kabuto are both very smart and have fatal moves, so it would be like a game of cat and mouse. Secondly Kurenai, because i think it would be awsome for a Genjutsu user and Medical ninja to go head to head.

Omantye. Thread over.

Sea Reapers, spell casting and fast swimmers= a dead Kabuto... oh wait... Naruto?

Gaara. He kill everyone.

Good point