Sasuke is really mediocre. He provides a good boost yes, but he is also very slow. And fox is a damage per second game and not damage per turn game. It doesn't sound like you have the better options thou, but WB asuma, GNW tenten, darui and hashi all have potential to be better. Some of those might lower your damage per fight but will make the fights shorter so you can get an extra fight in which nets more damage overall.